Application Finder

Brilliant Blue (BB) FCF, more commonly known as FD&C Blue #1, is the most commonly used blue dye worldwide for food and beverages. It is generally accepted as safe and non-toxic. Aside from foods labelled as organic or as free from artificial dyes, there is little objection to the use of BB at levels at or exceeding 100 μg/g in foods.This application for Misa (Metrohm Instant SERS Analyzer) is unique. The benefit is twofold — successful detection of a fluorescent dye, and a unique sample cleanup technique that permits detection of a target that does not exhibit a strong SERS signal and is present in a complex matrix. While Misa successfully detects BB in direct sampling, this application describes a simple extraction method that improves detectability of BB with Misa.

Monitoring the range of organic acids in wine is crucial to improve flavor and quality, and to fulfill universal standardized criteria such as the International Code of Oenological Practices. Analytically, organic acids can be properly determined with ion chromatography (IC) and suppressed conductivity detection. As a multicomponent method, inorganic acids can also be resolved which are also valuable tracers for wine quality and taste. This Application Note presents two IC methods for wine quality analysis: a fast isocratic screening method of major organic acids and anions including sulfite, and a complex monitoring method with a binary gradient to separate 15 organic acids. Inline Ultrafiltration was used for economical sample treatment.

Raman spectroscopy is used widely by law enforcement as a field screening tool due to its speed, selectivity and ease of use. The majority of materials can be identified by the Raman signature, as they exhibit sharp distinctive peaks serving as a molecular fingerprint. However, many street and real-world samples are dark in color and not pure. The dark color, often due to impurities, gives rise to fluorescence that interferes with the Raman measurement. One method to suppress the fluorescence of a sample and enhance the Raman activity / signal is by the use of Surface-Enhanced Raman Spectroscopy (SERS).

A new Raman system design is presented that expands the applicability of Raman to See Through diffusely scattering media such as opaque packaging materials, as well as to measure the Raman spectrum and identify thermolabile, photolabile, or heterogeneous samples.

The two most common mathematical representations used with handheld Raman spectroscopy as decision-making tools for spectroscopic data: Hit Quality Index (HQI) and significance level (p-value) are presented.

Forensics testing of samples encountered by law enforcement and customs agents is based on analytical techniques that are now being miniaturized and simplified and are making their way into field instrumentation. Field testing with Raman spectroscopy allows users to conduct reliable measurements at the point of arrest, reducing the burden on crime labs and accelerating the prosecution process.

The RVM method requires only a few spectra to make a model and can be quickly developed on the NanoRam-1064. Multivariate analysis of the Raman spectra on handheld Raman instruments provides more robust methodologies for identifying samples.

In this case study, a suspected counterfeit Adderall pill was measured directly with a TacticID Mobile using a point-and-shoot adapter. The spectra of the suspected couterfeit pill was found to contain cellulose and caffeine, but not the active ingredient. The TacticiD Mobile with 1064-nm laser excitation provides fluorescence suppression, giving those on the front lines a tool in the fight against dangerous counterfeit drugs.

Determination of N-acetylcysteine and phenylalanine in tablets against sinusitis by anion chromatography with UV/VIS detection according to USP.

Ion chromatography is a flexible technique with a large selection of intended uses in the pharmaceutical industry. – A few development trends and the latest advances are displayed here.

Handheld Raman is ever evolving. The combination of large libraries, a compact and easy-to-use system, and predictive Hazmat software make MIRA DS a powerful tool for defense and security professionals. Identify on-site materials, get hazard information, and make quick decisions about response to dangerous situations.

Accurate, reliable determination of ionic surfactants with the Epton two-phase titration method can be achieved using an OMNIS system as shown in this study.

The content of organic matter, limestone, silt, clay, and sand, along with pH value and exchangeable calcium and magnesium in soil can be determined in seconds with NIRS.

In power plants, corrosion is the greatest enemy. If corrosive impurities are present in the circuit streams (e.g., chlorides and hydroxides), deposition of an insulating layer of scale on the heat transfer surfaces occurs, resulting in costly and critical downtimes. To ensure high throughput of power plants, online analysis of critical parameters such as sodium is highly advantageous for safety, protection, and process optimization. With the 2035 Process Analyzer from Metrohm Process Analytics, operators gain the information they need to accurately identify trends, reduce downtimes, and address operational issues before costly problems arise.

Compounded injections of sodium bicarbonate are sterile solutions for correcting metabolic acidosis and other conditions requiring systemic alkalinization. Compounded injections of sodium phosphates serve as a phosphate source to either prevent or correct hypophosphatemia in patients with restricted oral intake. Ion chromatography (IC) with suppressed conductivity detection is the standardized way to accurately quantify sodium in these solutions.

The assay of calcium acetate, often used as a phosphate binder for dialysis patients, can be performed with ion chromatography (IC) as per USP <621> and <1225>.

Due to its price and wide availability, the anionic surfactant sodium lauryl sulfate (SLS; SDS) can be found in many detergents as an emulsifier or as a fat solvent e.g., in cleaning or cosmetic products. To avoid causing severe dry skin and hair, and thus skin irritation, regulations in many countries have restricted the sodium lauryl sulfate concentration in ready-to-use products to a range between 0.05–2.5% SLS. To control the concentration of SLS in different products, a titration is carried out with TEGO® trant A100 and the Optrode. The evaluation is done automatically by means of a software, leading to reliable and reproducible results.

Raman spectroscopy is used for material characterization by analyzing molecular or crystal symmetrical vibrations and rotations that are excited by a laser, and exhibit vibrations specific to the molecular bonds and crystal arrangements in the molecules. Raman technology is a valuable tool in distinguishing different polymorphs. Examples of portable Raman spectroscopy for identification of polymorphs and in monitoring the polymorphic transiton of citric acid and its hydrated form are presented.

Portable Raman spectroscopy is an invaluable tool in the study of archaeological sites, allowing for in situ analysis which minimizes the impact of such studies on important cultural sites. The flexibility of the use of a fiber optic probe and tripod-mounted video microscope with a light weight instrument reduces the need for sampling, and increases the ability to make representative measurements over what can be very large sample areas. The information content of Raman spectroscopy aids in the understanding of the materials used in the construction and restoration of important archaeological sites, and in understanding the degradation that is occurring which should aid in preservation and restoration work.

Portable Raman is used to quantify trigonelline, an alkaloid that contributes to the health benefits of some foods. A simple method to quantify the presence of diluted trigonelline in solutions using surface enhanced Raman spectroscopy is described. Portable Raman is a tool that could be used in quality control of food items such as coffee and quinoa.

The suitability and potential of Raman spectroscopy in forensics is widely known by forensic specialists who use it in the laboratory to identify a wide variety of compounds including explosives, drugs, paints, textile fibers and inks. However, the use of laboratory-grade Raman outside the laboratory, such as for in‐situ analysis at a crime scene, was something thought possible only in forensic‐fiction until just a few years ago. Fortunately, modern portable Raman spectrometers are commercially available, and their instrumental features are comparable to Raman lab‐ spectrometers.To prove this, some extraordinarily demanding and challenging applications, in which an in‐situ standoff identification of samples might be advisable, were tested.

Edible oils are not only a major source of nutrition but also a key basic material in the food industry. Vegetable oils are increasingly important because of their high content in mono- and polyunsaturated fatty acids in comparison with animal fats. In this application note, the main ingredients of olive oil, camellia oil, arachis oil, sunflower seed oil, and colza oil are analyzed using a portable Raman spectrometer combined with chemometrics software.

By means of azide analysis in Irbesartan a simple, fast, precise and accurate ion chromatographic method for the determination of traces of inorganic contaminants in pharmaceuticals is described. Traces of toxic azides in pharmaceutical products can accurately be determined in the sub-ppb range after Metrohm Inline Matrix Elimination using isocratic ion chromatography (IC) with suppressed conductivity detection. While the azide anions are retained on the preconcentration column, the interfering pharmaceutical matrix is washed away by a transfer solution, ideally consisting of 70% methanol and 30% ultrapure water. The analytical setup provides a well-resolved azide peak and thus alleviates the common drawback of excipient interferences, especially from the nitrate anion. Calibration with azide standards is linear over the range of 5…80 ppb, providing a coefficient of determination of 0.9995. The limit of detection (LOD) and the limit of quantification (LOQ) of azide in Irbesartan are 5 and 30 µg/L respectively; the relative standard deviations (RSD) for the peak area, peak height and retention time being smaller than 3.9%. Robustness testing involved variation of column oven temperature and composition of the transfer solution and, in terms of peak area, provided RSDs smaller than 2.8% and 3.1% respectively.

Metal precipitation and cyanide recovery in the SART process (sulfidization, acidification, recycling, thickening) depend to a great extent on the sulfide concentration. Among the flow injection analysis methods coupled to wet-chemical analyzers, the combination of a gas diffusion cell with an ion chromatograph (IC) plus subsequent direct spectrophotometric detection has proven to be one of the most convenient methods of sulfide analysis.This paper deals with the determination of sulfide anions via the coupling of a gas diffusion cell to an IC with subsequent spectrophotometric detection.

The 800 Dosino controlled by tiamo™ or Touch Control can be used universally for dosing and liquid handling tasks in both the analytical laboratory or directly in the synthesis laboratory. This poster looks at three typical liquid handling applications, the synthesis of metal-organic compounds, the preparation of standards, and the determination of pharmaceutical ingredients.

Psychoactive gamma-hydroxybutyrate (GHB) and its prodrug gamma-butyrolactone (GBL) are substances that are increasingly abused as date-rape and recreational (party) drugs. Since the non-controlled GBL converts into the illicit GHB both in-vivo and in-vitro, their legal distinction is of crucial importance.For the forensic determination of illegally added GHB and GBL in commonly consumed beverages, this work presents a simple and sensitive method that employs direct-injection ion chromatography combined with spectrophotometric detection. The method allows to trace GHB-GLB interconversion, whether in vivo or in vitro lactone cleavage or intramolecular GHB esterification, and thus complies with pertinent requirements of law enforcement agencies.

The Rancimat method is a widely accepted method for the determination of the oxidation stability of natural fats and oils. Its main application is quality control in oil mills and the oil processing industry. At elevated temperatures and under the exposure of air, fatty acids are oxidized. The reaction products are absorbed in ultrapure water that is continually monitored for conductivity. After an induction period with slow reaction, the formation of volatile carboxylic acids is accelerated. At that time the conductivity begins to increase rapidly. Instead of investing weeks or months, the sample can be oxidized within a few hours.The method can also be used to determine the oxidation stability of solid foodstuffs that contain natural fats or oils. Frequently, a direct determination without extraction of the fat is possible, if the fat content exceeds a minimum level. In these cases, a simple and reliable assessment of the quality of the produced foodstuff is possible.A number of fat-containing solid foodstuffs such as almonds, peanuts, peanut-flavored puffs, potato chips, muffins, butter cookies, French fries, and instant noodles were successfully tested with the Rancimat method. The experiments revealed that the comminution of the sample is one of the most important steps. The grinding procedure of the tested samples was kept as simple as possible to avoid the use of expensive milling instrumentation.

The poster shows the use of Vis-NIR spectroscopy for the simultaneous quantification of cobalt content, solids content, relative density and viscosity in paint driers as an outstanding alternative to conventional wet chemical laboratory methods. The advantages of the expanded wavelength range over the visible range become clear in this application: the visible range (400 – 780 nm) correlates directly with the cobalt content; the NIR range (780 – 2500 nm) is used for determining the chemical and physical parameters.

Pharmaceutical analysis guarantees drug safety by providing information on the identity, content, quality, purity, and stability of pharmaceutical products using analytical chemistry. Ion chromatography (IC) offers a broad range of pharmacopeia-compliant applications for quality control, monitoring, and improving drug manufacturing.As a very accurate and versatile technique, IC meets the requirements of many pharmaceutical applications. IC is a USP-accepted standard method for the determination of active pharmaceutical ingredients (APIs), excipients, impurities,pharmaceutical solutions as well as pharmaceutical starting materials, finished pharmaceutical products (FPPs) and even body fluids.This poster describes some typical examples.

This poster presented jointly with USP at AAPS meeting shows the new USP method for zinc as per <591> using Ion Chromatography which is highly selective and sensitive. Selectivity is achieved by separation and further improved with PCR reaction. Sensitivity and wide linear quantification limit make the new USP method ideal for QA/QC. Automated PCR delivery makes the overall method performance easy to validate.

Potassium iodide (KI) is used to treat overactive thyroid and to protect the thyroid gland from the effects of radiation from inhaled or swallowed radioactive iodine. Currently, in the USP Potassium Iodide Monograph, iodide identification is performed by wet chemistry and assay by manual titration, which has a history of reduced precision and accuracy. As part of USP’s global monograph modernization initiative, an alternative selective and sensitive method was developed and validated – ion chromatography (IC). The proposed IC method can also be used for the identification test as an alternative to wet chemistry.

Fluoride is commonly used in dental products to help prevent tooth decay. When fluoride is present in high concentrations, these products are regulated by 21 CFR 355. Three fluoride compounds used in over the counter (OTC) anti‐cavity dental products are sodium fluoride, stannous fluoride and sodium monofluorophosphate (MFP). The assay of fluoride in these active ingredients and finished formulations are determined by manual titration, or by ion‐selective electrodes. As a part of USP’s global monograph modernization initiative, an alternative selective and sensitive method has been developed and validated – ion chromatography (IC). The proposed IC method can also be used for the identification test as an alternative to the wet chemistry method.

A high throughput automated system was developed to determine pH of culture media using a pH module equipped with an external flow cell. A custom septum-piercing, vented needle was developed to accommodate the shape and size of the customer sample vials. For this application, both accurate and precise pH measurements were required. The data presented in this document was collected by a customer as a part of their validation process and was provided for use with their consent.

LC-MS/MS quantification methods are commonly used to determine trace levels of organic compounds. However, highly polar reversed phases (RPs) lack sufficient retention for very polar compounds, or they fail for charged organics. Separation using ion chromatography (IC) and subsequent MS/MS detection is an innovative alternative approach that combines the fast elution and flexibility of the IC system with the excellent resolution and high sensitivity of the MS/MS detector. This poster presents a fast, robust and reliable IC-MS/MS method for the detection of HAAs and other ionic analytes using the high-end MS/MS system QTRAP 6500+ from SCIEX coupled to a the 940 Professional IC Vario One SeS/PP/HPG instrument. This analytical setup is able to identify and quantify the presence of HAAs at trace levels with LLODs between 0.02 μg/mL and 0.2 μg/L on a single HAA. This capability easily fulfills the sensitivity requirements specified in EU Drinking Water Directive, which specifies a maximum residue level (MRL) of 60 mg/mL for the sum of monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid present in the representative sample.

An automatic titration method is described using biamperometric endpoint indication for the determination of antimony in antimony-alloyed cable lead (approx. 1% Sb). A 0.01 mol/L KBrO3 solution is used as the titrant.

Zinc, such as that occurring as a constituent of light alloys, can be determined by precipitation titration with potentiometric endpoint indication. The determination of zinc in the presence of cadmium is also possible.2 K4[Fe(CN)6] + 3 ZnCl2 → K2Zn3[Fe(CN)6]2 + 6 KCl

A routine method for the determination of copper is described. After dissolving the sample and adding a KI/KCNS solution, the released iodine is back-titrated with thiosulfate. The endpoint indication is potentiometric.

The quantitative determination of the alkaloid nicotine, which is an essential constituent of the tobacco plant, can be carried out by polarography. The quantification limit is less than 0.1 mg/L in the polarographic vessel.

Silver is an important metal not only in jewelry and silverware but also in electrical conductors and contacts. The knowledge of the exact silver content in fine silver and silver alloys ensures that quality standards for jewelry and silverware are met. As for the plating industry, the knowledge of the amount of silver in silver plating baths helps to run the bath efficiently.While X-ray fluorescence (XRF) is a fast alternative to determine the silver content in fine silver and silver alloys, it can only determine the silver content of the outermost sections of the metal. In contrast, titration offers a more comprehensive solution considering the whole sample, thus preventing fraud by thick plating.This application bulletin describes the potentiometric determination of silver in fine silver and silver alloys accordingto EN ISO 11427, ISO 13756, GB/T 17823, and GB/T 18996 as well as in silver plating baths by a titration with potassium bromide or potassium chloride, respectively

Indication of the titration endpoint of the weakly alkaline or weakly acidic terminal groups in non-aqueous solution is frequently not easy. An improvement is possible by using a suitable titrant (TBAH = tetrabutylammonium hydroxide for terminal carboxyl groups; perchloric acid for terminal amino groups).An improvement in the evaluation can also be achieved by choosing benzyl alcohol as the solvent.The choice of electrode combination and the measuring setup is also important. Differential potentiometry using the three-electrode technique results in a great improvement in titrations in poorly conducting solutions. Noisy signals are eliminated.

The quality of egg-based pasta is primarily determined by its egg content. Also of importance, however, is the water content, which influences the storage life of the product, as well as the degree of acidity which, in the case of high values, indicates undesirable acidification during processing or drying. A check of the chloride content shows whether salt has been added to the pasta.

The photometric determination of nitrate is limited by the fact that the respective methods (salicylic acid, brucine, 2,6-dimethyl phenol, Nesslers reagent after reduction of nitrate to ammonium) are subject to interferences. The direct potentiometric determination using an ion-selective nitrate electrode causes problems in the presence of fairly large amounts of chloride or organic compounds with carboxyl groups. The polarographic method, on the other hand, is not only more rapid, but also practically insensitive to chemical interference, thus ensuring more accurate results. The limit of quantification depends on the matrix of the sample and is approximately 1 mg/L.

This Bulletin is a supplement to Application Bulletin no. 36 (Half-wave potentials of inorganic substances) in the sense that the half-wave potentials of 100 different organic substances are listed. At the same time the supporting electrolytes used and the limits of determination are given.The various substances are listed in alphabetical order. The most important polarographically active functional groups are taken into consideration. This means that substances for related structures can also be determined polarographically in the same or similar supporting electrolytes, although they may not appear in the list.Unless otherwise stated, the half-wave potentials refer to a temperature of 20 °C, and the potentials are given in volts, measured with a sat. KCI-Ag/AgCl electrode assembly.The determination limits give the smallest concentrations which can be measured without risking serious errors in the results. In all cases, the limit of detection lies below the limit of determination.

This Application Bulletin describes the voltammetric determination of the elements antimony, bismuth, and copper. The limit of detection for the three elements is 0.5 ... 1 µg/L.

This Application Bulletin gives an overview of the volumetric water content determination according to Karl Fischer. Amongst others, it describes the handling of electrodes, samples, and water standards. The described procedures and parameters comply with the ASTM E203.

This Bulletin describes potentiometric titration methods for the determination of the acidity in milk and yoghurt according to DIN 10316, ISO/TS 11869, IDF/RM 150, ISO 6091 and IDF 86, the chloride content in milk, butter and cheese according to EN ISO 5943, IDF 88, ISO 15648, IDF 179, ISO 21422, and IDF 242. Additionally the determination of the sodium content in milk using the thermometric titration is described. The determination of the oxidation stability of butter in accordance to AOCS Cd 12b-92, ISO 6886 and GB/T 21121 as well as the determination of lactose in lactose free milk by ion chromatography is also described.For the determination of the pH value in dairy products see Application Bulletin AB-086 and for the determination of calcium and magnesium see Application Bulletin AB-235.

This Application Bulletin describes the determination of mercury by anodic stripping voltammetry (ASV) at the rotating gold electrode. With a deposition time of 90 s, the calibration curve is linear from 0.4 to 15 μg/L; the limit of quantification is 0.4 μg/L.The method has primarily been drawn up for investigating water samples. After appropriate digestion, the determination of mercury is possible even in samples with a high load of organic substances (wastewater, food and semi-luxuries, biological fluids, pharmaceuticals).

In addition to its natural occurrence in fruit and vegetables, ascorbic acid (Vitamin C) is used as an antioxidant in foods and drinks. Ascorbic acid is furthermore also to be found in numerous drugs.Ascorbic acid and its salts and esters can be determined with titration or by using polarography, for which ascorbic acid is oxidized to form dehydroascorbic acid.Bi-voltammetric or photometric equivalence point indication can be used for titrimetric determination. It must be taken into account here that only bi-voltammetric indication is independent of the inherent color of the sample. Polarography is the most selective of the methods described, as other reducing or oxidizing substances are not recorded.

This document outlines complexometric and potentiometric determination of metal ions via EDTA titration using a copper-selective electrode (Cu-ISE) with a durable epoxy shaft and crystal membrane. Because the electrode is insensitive to complexing agents, a preformed Cu–metal complex must be introduced into the sample prior to analysis. The method, applicable to direct or back-titration, exploits EDTA–metal formation constants to define equivalence points and enables quantification in several different matrices.

This Application Bulletin describes a polarographic method for the determination of cyanide that allows to determine free cyanide fast and accurately. The determination also succeeds in solutions containing sulfides, where other methods fail. Cyanide concentrations in the range b(CN–) = 0.01...10 mg/L cause no problems. Interference caused by anions and complexed cyanides has been investigated.

Cadmium, lead, and copper can be determined simultaneously in oxalate buffer by anodic stripping voltammetry (ASV) after digestion with sulfuric acid and hydrogen peroxide. Tin present in the sample does not interfere with the determination of lead.For the voltammetric determination of tin please refer to Application Bulletin no. 176.

This Application Bulletin describes methods for the polarographic and voltammetric determination of small quantities of chromium in water, effluent water and biological samples. Methods for the sample preparation for various matrices are given.

It has been known for years that consuming too much nitrates from foodstuffs can result in cyanosis, particularly for small children and susceptible adults. According to the WHO standard, the hazard level lies at a mass concentration c(NO3-) ≥ 50 mg/L. However, more recent studies have shown that when nitrate concentrations in the human body are too high, they can (via nitrite) result in the formation of carcinogenic and even more hazardous nitrosamines.Known photometric methods for the determination of the nitrate anion are time-consuming and prone to a wide range of interferences. With nitrate analysis continually increasing in importance, the demand for a selective, rapid, and relatively accurate method has also increased. Such a method is described in this Application Bulletin. The Appendix contains a cselection of application examples where nitrate concentrations have been determined in water samples, soil extracts, fertilizers, vegetables, and beverages.

This Bulletin describes a simple polarographic method for the determination of quinine in drinks and tablets. Whereas in drinks quinine can be determined directly, in the case of tablets it must first be extracted. The limit of quantification is 0.2 mg/L or 4 μg/tablet.

Nitrite can be determined polarographically after its conversion to diphenylnitrosamine (C6H5)2NNO. Potassium thiocyanate is used as a catalyst in order for the conversion to proceed rapidly and quantitatively. The reaction takes place in acid solution at a pH value of approx. 1.5. The limit of quantification is 5 μg/L NO2-.

This Application Bulletin describes a voltammetric method for the determination of aluminum in water samples, dialysis solutions, sodium chloride solutions and digestion solutions (e.g. of lyophilisates). The method utilizes the complexation of the Al3+ ion by Calcon (Eriochrome blue black R). The formed complex can easily be reduced electrochemically at 60 °C. The limit of quantitation depends on the purity of the reagents used and is approx. 5 µg/L.

Although the known photometric methods for the determination of ammonia/ammonium are accurate, they require a considerable amount of time (Nessler method 30 min, indophenol method 90 min reaction time). A further disadvantage of these methods is that only clear solutions can be measured. Opaque solutions must first be clarified by time-consuming procedures. These problems do not exist with the ion-selective ammonia electrode. Measurements can be easily performed in waste water, liquid fertilizer, and urine as well as in soil extracts. Especially for fresh water and waste water samples several standards, such as ISO 6778, EPA 350.2, EPA 305.3 and ASTM D1426, describe the analysis of ammonium by ion measurement. In this Application Bulletin, the determination according to these standards is described besides the determination of other samples as well as some general tips and tricks on how to handle the ammonia ion selective electrode. Determination of ammonia in ammonium salts, of the nitric acid content in nitrates, and of the nitrogen content of organic compounds with the ion-selective ammonia electrode is based on the principle that the ammonium ion is released as ammonia gas upon addition of excess caustic soda:NH4+ + OH- = NH3 + H2OThe outer membrane of the electrode allows the ammonia to diffuse through. The change in the pH value of the inner electrolyte solution is monitored by a combined glass electrode. If the substance to be measured is not present in the form of an ammonium salt, it must first be converted into one. Organic nitrogen compounds, especially amino compounds are digested according to Kjeldahl by heating with concentrated sulfuric acid. The carbon is oxidized to carbon dioxide in the process while the organic nitrogen is transformed quantitatively into ammonium sulfate.

This Application Bulletin describes a simple polarographic method to determine monomeric styrene in polymers. The limit of determination lies at 5 mg/L. Before the determination, styrene is converted to the electrochemically active pseudonitrosite using sodium nitrite.

This Bulletin describes three potentiometric, one photometric, one thermometric and one conductometric titration method for sulfate determination. The question of which indication method is the most suitable depends primarily on the sample matrix.Method 1: Precipitation as barium sulfate and back titration of the Ba2+ surplus with EGTA. Use of the ion-selective calcium electrode as indicator electrode.Method 2: As with Method 1, although with the electrode combination tungsten/platinum.Method 3: Precipitation titration in semi-aqueous solution with lead nitrate in accordance with the European Pharmacopoeia using the ion-selective lead electrode as indicator electrode.Method 4: Photometric titration with lead nitrate, dithizone indicator and the Optrode 610 nm, particularly suitable for low concentrations (up to 5 mg SO42- in the sample solution).Method 5: Thermometric precipitation titration with Ba2+ in aqueous solution, particularly suitable for fertilizers.Method 6: Conductometric titration with barium acetate in accordance with DIN 53127

This Application Bulletin describes the determination of water in non-explosive and non-flammable gaseous samples using the coulometric Karl Fischer method. This method is ideal for very low water contents.

Application Bulletin AB-076 contains a description of the polarographic determination of low concentrations (1–100 mg/L) of NTA and EDTA in bodies of water. NTA, EDTA and citrate have gained in importance as complexing agents and builders due to the fact that the laws of some countries have made it necessary to find a substitute for phosphates in detergents.This Bulletin describes the determination of larger quantities of complexing agents in detergents using potentiometric titration. The ion-selective copper electrode (Cu-ISE) is used here as the indicator electrode. The determination of complexing agents is not disturbed by the other constituents often present in detergents.

"Molybdenum is an essential trace element for plant growth. Since it occurs in natural waters only in trace amount, a very sensitive method of determination is needed. Using the following polarographic method, it is possible to determine 5·10-10 mol/L resp. 50 ng/L.The principle of the method is based on the reaction between the molybdate ion MoO42- and the complexing agent 8-hydroxy-7-iodo-quinoline-5-sulfonic acid (H2L) to form a MoO2L22- complex, which is adsorbed on the mercury electrode. The adsorbed Mo(VI) is reduced electrochemically to the Mo(V) complex. The hydrogen ions present in the solution oxidize Mo(V) again spontaneously to form the Mo(VI) complex, which is thus newly available for electrochemical reduction. This catalytic reaction is the reason for the high sensitivity of the method.Tungsten W(VI) exhibits practically the same electrochemical behavior as molybdenum, but is not described in detail in this Application Bulletin."

The bromine number and bromine index are important quality control parameters for the determination of aliphatic C=Cdouble bonds in petroleum products. Both indices provide information on the content of substances that react withbromine. The difference between the two indices is that the bromine number indicates the consumption of bromine in gfor 100 g sample and the bromine index in mg for 100 g sample.This Application Bulletin describes the determination of the bromine number according to ASTM D1159, ISO 3839, BS2000-130, IP 130, GB/T 11135 and DIN-51774-1. The bromine index determination for aliphatic hydrocarbons is described according to ASTM D2710, IP 299, GB/T 11136 and DIN 51774-2. For aromatic hydrocarbons the determination of the bromine index is described according to ASTM D5776 and SH/T 1767. UOP 304 is not recommended for the determination of the bromine number or bromine index because its titration solvent contains mercuric chloride.

After the degradation of biological samples (e.g. milk, wool, etc.), it is often important to know the cystine/cysteine ratio. This Application Bulletin describes the simultaneous, polarographic determination of the two amino acids. The determination is performed in perchloric acid solution at the DME. Samples with a high protein content require that the determination is performed in an alkaline solution.

This Application Bulletin describes the determination of the thermostability of PVC in accordance with ISO 182 Part 3 using the dehydrochlorination method with the 895 Professional PVC Thermomat. The instrument permits fully automatic determination of the stability time. The test is suitable for monitoring the manufacture and processing of PVC products manufactured in the injection molding process, for their final clearance, characterization and for the comparison of PVC products and for testing the effectiveness of heat stabilizers.

This Application Bulletin describes the stripping analysis of Ag at the rotating disk electrode (RDE) with glassy carbon tip (GC) or Ultra Trace graphite tip. In routine operation, the determination limit lies at approx. 10 μg/L Ag, with careful work 5 μg/L Ag can be obtained. After appropriate digestion, silver determination is also possible with samples containing a relatively high proportion of organic substances (e.g. wine, foodstuffs etc.). The method has been developed primarily for water samples (well, ground and wastewater, desilvering solutions of the photographic industry).

Only coulometric Karl Fischer titration can determine low water contents with sufficient accuracy.This Application Bulletin describes the direct determination according to ASTM D6304, ASTM E1064, ASTM D1533, ASTM D3401, ASTM D4928, EN IEC 60814, EN ISO 12937, ISO 10337, DIN 51777, and GB/T 11146. The oven technique is described according to ASTM D6304, EN IEC 60814, and DIN 51777.

This Application Bulletins describes the determination of nicotinamide (vitamin PP), a vitamin of the B series. Instructions for the determination in solutions (e.g. fruit juice), vitamin capsules and multivitamin tablets are given. The linearity range of the determination is also specified. The limit of detection is approximately 50 μg/L nicotinamide.

This Application Bulletin describes the polarographic determination of folic acid, a vitamin of the B series, also known as vitamin B9 or vitamin BC. Instructions for the determination in solutions (e.g. fruit juice), vitamin capsules and multivitamin tablets are given. The linear range of the determination is also specified. The limit of detection is approx. 75 µg/L folic acid.

This Application Bulletins describes the polarographic determination of thiamine (vitamin B1). The procedure allows an analysis in monovitamin preparations. The linear range of the determination is also given. The limit of detection is approx. 50 µg/L thiamine.

This Application Bulletin describes the polarographic determination of riboflavin (vitamin B2). The procedure allows an analysis in monovitamin preparations. The limit of determination is approx. 100 μg/L.

This Application Bulletin describes …

This Application Bulletins describes the polarographic determination of pyridoxine (vitamin B6). The method given allows determination in monovitamin and in some multivitamin preparations. The linear range of the analysis is also specified. The limit of detection is approx. 100 µg/L pyridoxine · HCI.

The effectiveness of antioxidants can be expressed as antioxidant activity. It can be readily determined using the Rancimat method. This is accomplished by first determining the induction time of a mixture made up of hog fat and the antioxidant to be investigated and then by determining the corresponding time for hog fat alone. The quotient expresses the efficiency of the respective antioxidant and is referred to as the antioxidant activity index (AAI).This Application describes the determination of the antioxidant activity index of five common antioxidants.

This Application Bulletin describes the determination of cadmium and lead at a mercury film electrode (MFE) by anodic stripping voltammetry (ASV). The mercury film is plated ex situ on a glassy carbon electrode and can be used for up to one day. With a deposition time of 30 s, the limit of detection is ß(Cd2+) = 0.02 µg/L and ß(Pb2+) = 0.05 µg/L. The linear working range for both elements goes up to approx. 50 μg/L using the same deposition time.

Chlorine is frequently added to drinking water for disinfection. Depending on the reactivity and the concentration of chlorine, toxic disinfection by-products (DBPs) can thereby be released. Therefore, it is necessary to strictly control the chlorine concentration in the drinking water. This Application Bulletin shows how to determine the chlorine concentration according to three standard methods: DIN EN ISO 7939-1, APHA 4500-Cl Method B, and APHA 4500-Cl Method I.

This Application Bulletin describes the determination of zinc at a mercury film electrode (MFE). Zinc can also be determined simultaneously with cadmium and lead. The determination of copper at the MFE is not possible. The mercury film is plated ex-situ on a glassy carbon electrode and can be used for half a day up to one day.Zinc can be determined at the mercury film electrode by anodic stripping voltammetry (ASV). The presence of copper, which is naturally present in many samples, affects the determination of zinc due to the formation of an intermetallic compound. As a result the determined concentrations of zinc are too low. The addition of gallium can eliminate the interference to a certain extent since the intermetallic complex of gallium and copper is more stable than the complex of zinc and copper.With a deposition time of 10 s, the limit of detection is β(Zn2+) = 0.15 μg/L. The linear working range goes up to approx. 300 μg/L.With the deposition time of 10 s the method is suitable for samples between 10 μg/L and 150 μg/L Zn content. For samples with lower concentrations the results are more reliable if the deposition time is increased to e.g. 30 s. Samples with higher concentrations have to be diluted.

This Application Bulletin describes the determination of titanium by adsorptive stripping voltammetry (AdSV) using mandelic acid as complexing agent. The method is suitable for the analysis of ground, drinking, sea, surface and cooling waters, in which the concentration of titanium is of importance. The methods can, of course, also be used for the trace analysis in other matrices.The limit of detection is approx. 0.5 µg/L.

The present Bulletin offers an overview of the multitude of surfactants and pharmaceuticals that can be determined with potentiometric titration. Metrohm provides five different surfactant electrodes for indicating the titration endpoint: the Ionic Surfactant, the High Sense, the Surfactrode Resistant, the Surfactrode Refill and the NIO Surfactant electrode. The manufacture of the respective titrants and their titer determination are described in detail. In addition to this, the Bulletin contains a tabular overview of more than 170 proven applications from the area of surfactant and pharmaceutical analysis. This guideline leads you reliably to your destination: At a glance you can see from the table which surfactant electrode and which titrant are optimally suitable for your product.

Two-phase titration with potentiometric indication is a universal method for the determination of ionic surfactants in detergents. The results obtained are comparable to those with the classic two-phase titration in accordance with Epton (mixed indicator system disulfine blue / dimidium bromide). The present Bulletin addresses various parameters that could have an influence on potentiometric surfactant titration. The information provided makes it possible for the user to determine precisely the anionic surfactant content in practically all formulations.

Generally speaking, the gas extraction or oven method can be used for all samples which release their water when they are heated up. The oven method is indispensable in cases in which the direct volumetric or coulometric Karl Fischer titration is not possible, either because the sample contains disruptive components or because the consistency of the sample makes it very difficult or even impossible to transfer it into the titration vessel.The present Application Bulletin describes automatic water content determination with the aid of the oven technique and coulometric KF titration, using samples from the food, plastic, pharmaceutical and petrochemical industry.

In an acidic solution (containing NH4F * HF, Al(NO3)3 / KNO3) sodium forms NaK2AlF6 which precipitates in an exothermic solution, enabling analysis by thermometric titration. Several foods were analyzed, namely bouillon, gravy, tomato ketchup, corn chips, pretzel sticks as well as crackers. The reproducibility of the results was good. After weighing in and adding solutions, samples were crushed with a polytron to ensure homogeneity in the measuring solution. Relative standard deviations were between 0.08% and 3.75%. In addition to this application bulletin, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs

The presented Application Bulletin describes the apparatus and methods that are used for acid-base analysis of whole blood and blood plasma by Joergensen and Stirum. Evaluation of the measured data is performed with a software sold by Komstar AG.

This Application Bulletin describes two methods for the determination of iron at the Multi Mode Electrode.Method 1, the polarographic determination at the DME, is recommended for concentrations of β(Fe) > 200 μg/L. For this method the linear range is up to β(Fe) = 800 μg/L.For concentrations < 200 μg/LMethod 2, the voltammetric determination at the HMDE, is to be preferred. The detection limit for this method is β(Fe) = 2 μg/L, the limit of quantification is β(Fe) = 6 μg/L. The sensitivity of the method cannot be increased by deposition.Iron(II) and iron(III) have the same sensitivity for both methods.These methods have been elaborated for the determination of iron in water samples. For water samples with high calcium and magnesium concentrations such as, for example, seawater, a slightly modified electrolyte is used in order to prevent precipitation of the corresponding metal hydroxides. The methods can also be used for samples with organic loading (wastewater, beverages, biological fluids, pharmaceutical or crude oil products) after appropriate digestion.

This bulletin discusses automated determination of sodium in milk products available to the public using a 859 Titrotherm and a 814 USB Sample Processor. The sodium content of milk can be rapidly and easily titrated thermometrically with a standard solution of Al3+ as titrant. Thermometric titrations are conducted under conditions of constant titrant addition rate. The molarity of the titrant is computed automatically in tiamoTM (software) with the SLO command. Results are reported as mg Na/100 mL. In addition to this application bulletin, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs

This Application Bulletin describes the method of near-infrared spectroscopy in diffuse reflection for the purpose of determining residual moisture in a lyophilized pharmaceutical product. Numerous sample vials containing freeze-dried pharmaceuticals were spiked with varying amounts of water for calibration purposes. The resulting differences in the absorption wavelengths of the OH-oscillation were correlated with the water content determined by Karl Fischer titration using the algorithm of multiple linear regression (MLR).

The determination of the acid number plays a significant role in the analysis of petroleum products. This is manifested in the numerous standard procedures in use over the world (internal specifications of multinational companies, national and international specifications of ASTM, DIN, IP, ISO, etc.). These procedures differ mainly in the composition of the used solvents and titrants.This bulletin describes the determination of the acid number in petroleum products by applying different types of titration.The potentiometric determination is described according to ASTM D664, the photometric according to ASTM D974 and the thermometric titration according to ASTM D8045.

This Application Bulletin shows the determination of the total base number in petroleum products by applying different titration types according to various standards.

This Application Bulletin provides information regarding the MATi 10 (Metrohm Automated Titration) system. MATi 10 is a completely configured system for automatic volumetric Karl Fischer titration with which the water content in liquid and solid samples can be determined. Up to 24 samples can be analyzed directly in 75 mL titration vessels. The samples are weighed into the titration vessels and covered with an aluminum foil. This prevents falsification of the water content.

The present Application Bulletin contains NIR applications and feasibility studies for NIRSystems devices in the chemical industry. Qualitative and quantitative analyses of a wide variety of samples are part of this bulletin. Each application describes the instrument that was originally used for the analysis, as well as the system recommended for the analysis and the results that were achieved thereby.

The present Application Bulletin contains NIR applications and feasibility studies using NIRSystems devices in the pharmaceutical industry. Qualitative and quantitative analyses of a wide variety of samples are part of this bulletin. Each application describes the instrument that was originally used for the analysis, as well as the system recommended for the analysis and the results that were achieved thereby.

Near-infrared spectroscopy is used for a wide range of analyses. Thanks to its fast and non-destructive determination, NIRS is outstandingly suited to quality control of products and raw materials, whether during production or on the finished product. This Application Bulletin shows NIR applications and feasibility studies from the lacquer and paint industry performed using NIRSystems devices.

The present Application Bulletin contains NIR applications for the determination of important parameters for pulp and paper quality analysis. Each application describes the instrument that was originally used for the analysis, as well as the system recommended for the analysis and the results that were achieved thereby.

The present Application Bulletin describes applications that use near-infrared spectroscopy. Each application describes the used and alternatively deployable spectrometer as well as analysis conditions and results and, where available, information on feasibility studies.

The present Application Bulletin elucidates several applications for the polymer industry that can be carried out with the aid of NIR instruments. This Bulletin contains analyses of a wide range of parameters in a very large array of samples. The hydroxyl number is one of the best-known of the parameters that can be determined rapidly using near-infrared spectroscopy. The determination of the hydroxyl number in different areas and in different polyol types is also a part of this Bulletin. Each application describes the sample and the instrument that was originally used for the analysis, as well as the recommended instruments and the results.

This Application Bulletin describes the determination of arsenic in water samples by anodic stripping voltammetry using the scTRACE Gold sensor. This method makes it possible to distinguish between As(total) and As(III). With a deposition time of 60 s, the limit of detection for As(total) is 0.9 µg/L, for As(III) it is 0.3 µg/L.

The Application Bulletin describes the determination of suppressor in acid copper baths by smartDT. The determination of suppressor with dilution titration (DT) involves numerous additions with standard solution or sample to reach the evaluation ratio. Usually fixed, equidistant addition volumes are used. With smartDT, variable addition volumes are used that are dynamically calculated by the software. At the beginning, the volumes are bigger. Towards the evaluation ratio, the addition volume becomes smaller to guarantee a good accuracy of the result. The operator defines the first and the smallest addition volume to be used. All volumes in between are calculated by the software considering the progress of the determination. The time saving with smartDT compared to a classic DT with fixed addition volumes can be up to 40%. smartDT is suitable for nonlinear regression and quadratic regression as well as linear interpolation. It can be used for determination of suppressor in acid copper baths as well as in tin and tin-lead baths and works with 1, 2, and 3 mm Pt working electrodes. A 800 Dosino is required for the automatic addition of suppressor standard or sample. The method can also be used in fully automated systems.

This Application Bulletin describes the determination of inorganic mercury in water samples by anodic stripping voltammetry using the scTRACE Gold sensor. With a deposition time of 90 s, calibration is linear up to a concentration of 30 µg/L; the limit of detection lies at 0.5 µg/L.

This Application Bulletin compares the unique focusing technology of the portable Metrohm Raman system "Mira" with conventional methods. The method described here is called Orbital Raster Scan (ORS). Experiments show the advantages of ORS technology, using determination and quantification of medicines as an example. It improves the reproducibility of the Raman signals from targeted, active, pharmaceutical ingredients (APIs) in effervescent, cold medicines. Shorter analysis times and an improved, consistent assignment of spectra of the known medicine with the help of a spectral library are further advantages of ORS technology.

This Application contains information regarding titer determination in Karl Fischer titration, in particular regarding the water standard suitable for a titer determination and for the correct handling of the same.Titer determination for Karl Fischer titrants is indispensable, because the titer is subject to changes caused by the humidity in the air. The frequency of the determination depends on the titrant and the tightness of the system.The titer has the unit mg/mL in Karl Fischer titration. The value calculated in a titer determination indicates how many milligrams of water react on one milliliter of titrant.

This Application Bulletin describes the determination of the total acid number in various oil samples by catalytic thermometric titration as per ASTM D8045.

Copper is one of the few metals which is available in nature also in its metallic form. This and the fact that it is rather easy to smelt led to intense use of this metal already in the so-called Copper and Bronze Age. Nowadays, it is more important than ever, because of its good electrical conductivity and its other physical properties. For plants and animals, it is an essential trace element; for bacteria, in contrast, it is highly toxic.This Application Bulletin describes the determination of copper by anodic stripping voltammetry (ASV) using the scTRACE Gold electrode. With a deposition time of 30 s, the limit of detection is about 0.5 μg/L.

This Application Bulletin describes the methods for the determination of uranium by adsorptive stripping voltammetry (AdSV) according to DIN 38406 part 17. The method is suitable for the analysis of ground, drinking, sea, surface and cooling waters, in which the concentration of uranium is of importance. The methods can, of course, also be used for the trace analysis in other matrices.Uranium is determined as chloranilic acid complex. The limit of detection in samples with low chloride concentration is about 50 ng/L and in seawater about 1 µg/L. Matrices with high chloride content can only be analyzed after reduction of the chloride concentration by means of a sulfate-loaded ion exchanger.

This Application Bulletin describes the voltammetric determination of the elements iron, copper and vanadium. Fe as well as Cu and V can be determined as catechol complex at the HMDE by adsorptive stripping voltammetry (AdSV). Fe(II) and Fe(III) are determined as Fe(total) with the same sensitivity for both species in either phosphate buffer or PIPES electrolyte. Cu and V can be determined in PIPES buffer.The methods are primarily suitable for the investigation of ground, drinking and surface waters, in which the concentration of these metals is important. But the methods can naturally also be used for trace analysis in other matrices.The limit of detection for all three elements in PIPES buffer is 0.5 ... 1 µg/L, for iron in phosphate buffer it is approx. 5 µg/L.

This Application Bulletin describes the determination of Sn(II) in presence of Sn(IV) by anodic stripping voltammetry (ASV). Using an electrolyte containing fluoride, Sn(IV) gives no signal, so that a speciation is possible. The limit of detection is 2.5 µg/L.

Lead is known to be highly toxic and lead salts are easily absorbed by creatures. By interfering with enzyme reactions,lead can affect all parts of the human body. It can cause severe damage to brain and kidneys and can cross the bloodbrain barrier. Cases of chronic lead poisoning caused by lead metal used in the water piping system are well known. Therefore, the control of drinking water for lead content is of utmost importance. In many countries (e.g., EU, USA), the limit for lead in drinking water is between 10 and 15 μg/L. These concentrations can reliably be determined with the method described in this Application Bulletin. The determination is carried out by anodic stripping voltammetry at a silver film applied to the scTRACE Gold electrode.

Heavy metals, particularly cadmium and lead, are known to be highly toxic to humans. Therefore, controlling the cadmium and lead content in drinking water is of utmost importance. In many countries, the limit in drinking water for cadmium is between 3–5 µg/L, and for lead it is between 5–15 µg/L. These trace concentrations can reliably be determined with the method described in this Application Bulletin. The determination is carried out by anodic stripping voltammetry (ASV) using the non-toxic Bi drop electrode in a slightly acidic electrolyte.

Iron is an essential element in the human diet and is found in many natural and treated waters. Therefore, the World Health Organization (WHO) does not issue a health-based guideline value for iron. Higher concentrations of iron in surface waters can indicate the presence of industrial effluents or outflow from other operations and sources of pollution. Because of this, precise, rapid, and accurate iron determination at low concentrations in environmental and industrial samples is of great importance. This can be achieved with the method described in this Application Bulletin.

Cobalt is an essential element for humans because it is a component of vitamin B12. While small overdoses of cobalt compounds are only slightly toxic to humans, larger doses from 25–30 mg per day may lead to skin, lung, and stomach diseases, as well as liver, heart, and kidney damage, and even cancerous growths. The same is valid for nickel, which can lead to inflammation at higher concentrations. Drinking a large amount of water containing nickel can cause discomfort and nausea. In the EU the legislation specifies 0.02 mg/L as the limit value for the nickel concentration in drinking water. This concentration can be reliably determined with the method described in this Application Bulletin.

Pyrithione complexes, such as zinc pyrithione (ZnPT), copper pyrithione (CuPT), and sodium pyrithione (NaPT), are used as fungicides and bactericides. ZnPT is used in the treatment of skin conditions such as seborrheic dermatitis or dandruff. Furthermore, ZnPT is sometimes used as an antibacterial agent in paints to prevent algae and mildew growth. CuPT is primarily in use as a biocide to prevent biofouling of surfaces submerged in water. Meanwhile, NaPT is used as antifungal agent for treatment of mycosis, such as athlete’s foot. The different pyrithione complexes are determined by iodometric titration using a maintenance-free Pt Titrode for the indication.

The main components of a battery are the positive and negative electrodes, together with the electrolyte, which provides only the ionic conductivity. The most common electrolytes are in the liquid state. Therefore, a separator is needed to provide a physical separation between the electrodes. The separator is soaked with electrolyte. The MacMullin number is a parameter used to determine the quality of a separator, in terms of ionic conductivity, when soaked with an electrolyte. The MacMullin number can be calculated, using the results of data fitting of two EIS experiments and the geometric factors of the measurement cells. In this application note, a commercial electrolyte is employed, together with a porous filter, used as a separator.

In battery research, electrochemical impedance spectroscopy (EIS) is a necessary tool to investigate the processes occurring at the electrodes. With a common three-electrode battery, EIS can be performed sequentially first at one electrode and then at the other electrode.

In pressurized water reactors (PWRs), light water is used as primary coolant. Boron (as boric acid) readily absorbs neutrons and is added to the coolant to control reactivity. Lithium hydroxide assures a pH value greater than 7 to prevent corrosion. This application allows to measure sub-ppb levels of zinc, nickel, calcium, and magnesium besides high boric acid and lithium hydroxide concentrations.

In pressurized water reactors (PWRs), light water is used as coolant in the primary side. Boron (as boric acid) is added to the coolant to absorb neutrons, thus controlling reactivity. Lithium hydroxide assures the alkaline pH value to prevent corrosion. This application allows to measure lithium content besides high boric acid concentrations. AN-C-138 shows the respective trace metal determination on the same system setup.

1,3,5-trioxane is a heterocyclic compound formed by trimerization of formaldehyde. Trioxane is used for the production of polyformaldehyde plastics such as poly(oxymethylene) (POM) and solid fuels. Aqueous 1,3,5-trioxane solutions frequently contain trace triethylamine that requires quantification. This is performed on the Metrosep C 3 - 250/4.0 column with subsequent direct conductivity detection.

This application describes the determination of fluoride, chloride, bromide and sulfur (as sulfate) in an ethanol standard solution with halo organic (4-halogen benzoic acids; F, Cl and Br) and sulfur organic compounds (3-(Cyclohexylamino)-1-propanesulfonic acid) by means of Metrohm Combustion Ion Chromatography with flame sensor and Inline Matrix Elimination.Keyword: pyrohydrolysis

This Application Note looks at the determination of fluorine and sulfur in certified liquefied gas using Metrohm Combustion IC. Sequential determinations proceed in parallel to a certain extent: While the absorption solution of a sample that has already been combusted is being analyzed with IC, the combustion of the next sample is already underway.Keyword: pyrohydrolysis

Paraffin and lubricating oils are yielded from the wax fraction of raw oil distillation. The chloride content of both should be low. This Application Note describes chloride determination after inline combustion. Although it does not happen in this application, this method can also be used to quantify the sulfur content.Keyword: pyrohydrolysis

The burning of coal contaminates the atmosphere with halogens. Fluorine and chlorine are natural components of coal, whereas the bromide that is found therein is often adulterated as calcium bromide in order to reduce mercury emissions. This Application Note shows the results of combustion digestion with Combustion IC for three coal samples, each with a different bromide content.Keyword: pyrohydrolysis

Coal contains a certain amount of fluorine, chlorine, and sulfur compounds. During combustion of the coal, these components release corrosive acids (e.g., fluorine compounds form hydrofluoric acid). Thermal power plants therefore request low-fluorine coal to avoid massive hydrofluoric acid production. In this application note, fluorine content in coal is determined by ion chromatography after pyrohydrolysis.

Halobutyl rubber is frequently used in the production of pharmaceutical stoppers. It is ideal for this application due to its low permeability to gases and its chemical resistance. Chlorinated and brominated butyl rubber stoppers are analyzed for their halogen and sulfur content. Halogen and sulfur compounds are released by pyrohydrolysis and analyzed by subsequent ion chromatography (IC).

The content of organic chloride in crude oil is determined according to ASTM D8150 in the naphtha fraction after distillation. The naphtha fraction is washed with caustic and water, respectively, to remove hydrogen sulfide and inorganic halides. Here, the determination of organic chloride after inline combustion is presented. Although the sulfur content was of no interest in this application, the same setup allows sulfur quantification.

Iron ore is an important resource for steel production. Its natural content of halogens is a quality characteristic due to the corrosiveness of the respective halogenides. Combustion IC applying the sacrificial vial technology is used for the analysis of fluorine and chlorine in ore. WO3 usually is added to improve the release of SO2 and therefore sulfur recovery. In this application, it also significantly improves the recovery of fluoride.

Crude oil typically contains no organic halides. These are introduced at production sites, in pipelines, or in storage tanks. These components produce HF, HCl, and other acids in reforming and hydro-treating processes, leading to corrosion and catalyst poisoning. Speciation of the halides is an important parameter to measure in order to trace the contamination source. The current specifications expect to find less than 2 mg/kg organic chlorine in crude oil. Sulfur in crude oil could be quantified on the fly. Due to the specific request in this application, only the halogens are determined.

In textiles, the water-repelling effect may be introduced by different treatments, such as the application of fluorochemicals. These compounds, especially perfluoroorganic substances, are extremely persistent in the environment and are therefore listed as emergent contaminants. Combustion IC with pyrohydrolysis and subsequent ion chromatographic determination is applied to analyze the fluorine content in fabrics.

Cellulose ester foils are produced using chlorinated solvents. The residual amount of the solvent used in production evaporates within a few days in ambient conditions. The residual solvent is determined by combustion IC, through the conversion of organically bound chlorine to chloride by pyrohydrolysis. The final product needs to be free of all chlorinated solvents. Therefore, critical contents of such compounds can be detected in quality control analysis. Application of MiPT in this study has enabled an automated and precise calibration out of a single standard.

AOF (adsorbable organic fluorine) is used to screen for per- and polyfluorinated alkyl substances in aqueous matrices via pyrohydrolytic combustion and ion chromatography.

Combustion ion chromatography (CIC) measures AOX (adsorbable organically bound halogens, i.e., AOCl, AOBr, AOI) and AOF as well as CIC AOX(Cl) according to EN ISO 18127.

This Application Note is based on the ASTM standard G150, developed to test the resistance of stainless steel, and otheralloys related to stainless steel, on pitting formation at elevated temperature. This is achieved by determining the potential-independent critical pitting temperature (CPT), defined as the lowest temperature at which pitting evolution occurs. The CPT experiment consists of applying a potential to the specimen while the cell temperature is raised and recording the current.

In this Application Note, stepwise dissolution measurement (SDM) is applied to aluminum samples coated with different materials, in order to gain insights in corrosion protection. The combination of the Autolab PGSTAT204 with the 1 L Autolab corrosion cell and the NOVA software provides the suitable setup to perform SDM and other corrosion experiments.

In this Application Note, EIS is applied on three coated aluminium samples, before and after the stepwise dissolution measurement (SDM). This technique has been reviewed in the Application Note AN-COR-08.

The rotating cylinder electrode (RCE) is a technique used in corrosion research to simulate in a laboratory environment the turbulent flow which usually occurs when liquids are transported through pipelines. The RCE is used to generate a turbulent flow at the surface of a sample, simulating the pipe flow conditions. Experiments that involve an RCE are regulated by the ASTM G185 standard. In this application note, The RCE with a 1018 carbon steel cylinder sample was used with the linear polarization (LP) measurement technique.

The International Standard ISO 17463 describes the determination of the anticorrosive properties of high impedance organic protective coatings on metals. This technique uses cycles composed of electrochemical impedance spectroscopy (EIS) measurements, cathodic polarizations and potential relaxation. This application note shows the compliance of the Metrohm Autolab PGSTAT M204 and flat cell with the standard ISO 17463.

Tafel analysis is an important electrochemical technique used to understand reaction kinetics. By studying the Tafel slope, it reveals the rate-determining steps in electrode reactions, aiding fields like corrosion and fuel cell research. This method helps industries optimize processes and improve device performance by tailoring materials and conditions for greater efficiency.

Atorvastatin is a medication that is used for reducing cholesterol levels. A sensitive and reliable method for TBA detection is required, given that trace amounts of tetrabutylammonium (TBA) are to be found in the presence of atorvastatin and its derivatives. One such method is ion chromatographic separation on the Metrosep C Supp 1 - 250/4.0 with subsequent conductivity detection and sequential suppression.

The Autolab Electrochemical Quartz Crystal Microbalance (EQCM) is an optional module for the Autolab PGSTAT which can be used to control a 6 MHz crystal oscillator. This technique can be used to perform electrogravimetric measurements with detection limits in the sub μg range.

To improve the performance of electrochemical energy storage devices like batteries and supercapacitors, one can focus on enhancing the ion conductivity (ƠDC) of the electrolyte. It is a common method for obtaining ƠDC values of different electrolyte systems, to carry out electrochemical impedance spectroscopy (EIS) experiments, at different temperatures, in a 2-electrode setup.

The determination of heavy metal ions in a solution is one of the most successful application of electrochemistry. In this application note, anodic stripping voltammetry is used to measure the presence of two analytes, in a sample of tap water.

Capacitors are electronic components necessary for the success of the electronics industry. They have also become essential components of both electric and hybrid vehicles. Electrochemical tests, such as potentiostatic cyclic voltammetry, are used to check the performance of capacitors. VIONIC powered by INTELLO can perform both staircase and linear cyclic voltammetries (CV). This Application Note gives a comparison between the linear and the staircase potentiostatic cyclic voltammetries and highlights the necessity of using the linear CV to best study the performance of capacitors.

In this Application Note, hydrogen permeation experiments are conducted following the procedure described in the ASTM standard G148.

The Devanathan-Stachurski cell (or «H cell») is successfully used to evaluate the permeation of hydrogen through sheets or membranes. As small amounts of hydrogen pass through the sheet or membrane, a very sensitive potentiostat is required for its detection. A study of the hydrogen permeation properties of different iron sheets is discussed in this Application Note while taking the instrumental requirements into account.

By using an enzymatic sensor with a screen-printed electrode, producers can measure lactic acid production, thereby monitoring fermentation processes.

Spectro electrochemiluminescence experiments comparing photodiode and microspectrometer detectors, showing how each sensor captures ECL signals for the analysis of single and dual luminophore systems.

Zinc coatings are widely applied for medical devices and to protect steel against corrosion. Electrodeposition, modulated by electrochemical parameters and tailored additives such as polyethylene glycol (PEG), enables control over coating morphology, with PEG shown to delay deposition and promote smoother surfaces. This Application Note demonstrates that EQCM-D, integrated with electrochemical methods, provides detailed insight into Zn deposition and additive effects, supporting process optimization for coating performance.

PEDOT:PSS is a tunable, conductive coating whose properties depend on parameters such as counter-ion selection, secondary doping, and polymerization conditions. This Application Note demonstrates the combined use of EQCM-D, Raman spectroscopy, and electrochemical methods to monitor film growth, correlating frequency and dissipation changes across harmonics with in situ spectroscopic and electrochemical signals. The introduced probe-based EQCM-D platform enables simultaneous Raman acquisition, providing a powerful tool to design and optimize PEDOT:PSS coatings.

Here, the most common circuit elements for EIS are introduced which may be assembled in different configurations to obtain equivalent circuits used for data analysis.

Electrochemical impedance spectroscopy (EIS) is a powerful technique which provides information about the processes occurring at the electrode-electrolyte interface. The data collected with EIS are modeled with a suitable electrical equivalent circuit. The fitting procedure will change the values of the parameters until the mathematical function matches the experimental data within a certain margin of error. In this Application Note, some suggestions are given in order to get acceptable initial parameters and to perform an accurate fitting.

Alamar Blue is monitored with fluorescence spectroelectrochemistry during its irreversible reduction to resorufin and further reversible reduction to dihydroresorufin.

This Application Note explains how fluoride determination in acid etching baths can be performed with thermometric titration.

This Application Note describes a method for the determination of causticizer, carbonate and aluminum oxide in used Bayer process liquors. The method is based on processes that were developed by Watts-Utley and VanDalen-Ward.

Phosphorus is a primary macronutrient for plants and is a constituent of DNA and adenosine triphosphate (ATP), which is involved in many biological processes requiring energy. In fertilizers, phosphorus is present in the form of phosphate, as the most accessible form of phosphorus for plants is dihydrogen phosphate. Knowledge of the phosphorus content helps to select the right fertilizer for the plants.Traditionally, phosphate is determined gravimetrically (a time consuming procedure) or spectrophotometrically (expensive instrumentation). In this Application Note, an alternative method is presented, where phosphate is determined by a precipitation titration with magnesium. Various solid and liquid NPK fertilizers with phosphorus contents between 6.5 and 17% were analyzed. The analysis by thermometric titration requires no sample preparation in case of liquid NPK fertilizers and only minimal sample preparation in case of solid NPK fertilizers. One determination takes about 5 minutes.

Titration of an unfiltered suspension of the sample with a standardized solution of aluminum containing a stoichiometric excess of potassium ions in the presence of ammonium hydrogen difluoride at ~ pH 3 to give an exothermic reaction, forming insoluble NaK2AlF6. The titrant is standardized against a solution prepared from anhydrous sodium sulfate or sodium carbonate. In addition to this application note, you can find more information on thermometric sodium determination in foods in our application video available on YouTube: https://youtu.be/lnCp9jBxoEs

This Application Note describes the determination of fluoride in silicon etch solutions with thermometric titration.

Sulfate is precipitated by reaction with an acidified barium chromate solution. The excess barium chromate is precipitated by basification with ammonia solution. Residual soluble chromate equivalent to the sulfate content of the sample is titrated with a solution of standard ferrous ion to a thermometrically determined endpoint.

Sulfate is precipitated as barium sulfate by reaction with an acidified barium chromate solution. The excess barium chromate is precipitated by basification with ammonia solution. Residual soluble chromate, equivalent to the sulfate content of the sample, is titrated with a solution of standard ferrous ion to a thermometrically determined endpoint.

This Application Note supplements AN-H-003 with the treatment of the standard addition of sulfate as sulfuric acid. This technique may be contemplated when either sulfate levels are too low for a satisfactory direct titration, or when the sample matrix hinders endpoint detection, leading to poor precision and accuracy.

This Application Note describes the determination of the free and total hydroxide and aluminum oxide content in Bayer process and other aluminate liquors. The method is not subject to interference by carbonate ions. An aliquot of sodium aluminate liquor is titrated with potassium hydrogen carbonate solution to yield the free hydroxide ion content of the liquor.

This Application Note deals with the determination of ferric ion in acidic and copper-free solutions using thermometric titration. The ferric ion is reduced by iodide. The released iodine reacts exothermically when titrated with thiosulfate solution. The endpoint is determined through temperature plotting by the temperature sensor Thermoprobe.

This Application Note describes the determination of aluminum ion down to approximately 0.5 g/L in acidic solutions containing ferric, ferrous, and other ions whose hydroxides do not dissolve in strongly basic solutions.

This Application Note looks at the determination of ferrous ion in acidic solutions from approximately 0.25 g/L by thermometric titration with ceric titrant. The exothermic oxidation reaction shows a sharp endpoint that is detected using the Thermoprobe as a sensitive temperature sensor.

This Application Note describes the determination of total sodium content in canned fish products using thermometric titration. In addition to this application note, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs

This Application Note describes the determination of the total sodium content in instant noodles which are also called «two minute noodles» in some countries. These products contain considerable amounts of sodium (at least 50% of the recommended daily dosage), which means that precise analysis of the sodium content is required. Argentometric titration of the chloride content (assuming that the sodium content in the noodles originates exclusively from the sodium chloride that is added to them) is unsuitable for precise analysis, as the nutrient contents listed on the product packaging document the presence of additional sodium salts other than sodium chloride. Thermometric titration enables fast and direct determination of sodium. In addition to this application note, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs

This Application Note describes the determination of the total concentration of sodium in precursor solutions used in the manufacturing of margarine. The solutions of the precursors are mixed with edible fats and oils to make margarine. Traces of sodium chloride and other sodium and potassium salts may be added to the margarine during this process, usually in the form of emulsifiers, stabilizers, antioxidants, vitamins, coloring agents or flavor enhancers. The analysis of the total sodium content in the precursor solutions is more efficient and cost-effective for the manufacturers than later total sodium content analyses in the final product.As a rule, argentometric titration of chloride is used for indirect determination of the sodium content of foodstuffs. The assumption behind this approach is that the chloride ions are present in a molar ratio of 1:1 with the sodium ions. This is however not the case when – as is usually the case with foodstuffs containing sodium – additional compounds containing sodium are also present in the margarine. The use of potassium chloride as a partial replacement for sodium chloride in some formulations is an additional source of error.The direct titration of sodium by means of thermometric endpoint titration (TET) eliminates these problems. TET is a direct determination method that not only takes into account the entire sodium content present in the solution but is also not hampered by the presence of potassium ions. In addition to this application note, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs

This application note describes the determination of the total sodium content in soy milk products. The methodology may also be applied to the determination of sodium in milk products from cows, goats and sheep. A standard addition technique is employed to permit the accurate and precise determination of sodium at relatively low levels.

This Application Note describes the determination of aluminum in samples containing silicon dioxide using thermometric titration and EDTA as the titrant. Excess EDTA is titrated with a Cu2+ solution of known concentration. The initial, uncomplexed Cu2+ ions react immediately with the H2O2 present in the solution, leading to a recognizable sudden increase in temperature.

This Application Note looks at the determination of ferrous ion in acidic solutions through redox titration with potassium permanganate as titrant and thermometric titration.

This Application Note describes the determination of nitrite using thermometric endpoint titration with sulfamic acid. The nitrite content of a solution can be analyzed down to 0.2 mmol/L.

Sodium can be determined thermometrically in cheese without sample preparation and addition of additives. A homogenizer is responsible for distribution and stirring. In addition to this application note, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs

Thermometric titration is used to determine hydrochloric acid and hydrofluoric acid (hydrogen fluoride) in etching baths containing ethanol and acetonitrile. Two endpoints appear on the titration curve that are used individually for the quantification of the respective acid.

Thermometric titration is used to determine hydrofluoric acid and nitric acid in etching baths containing ethanol and acetonitrile. Two endpoints appear on the titration curve that are used individually for the quantification of the respective acid.

Metal-organic compounds are commonly used in organic chemistry, for example as Grignard reagents or as strong bases (e.g., butyl lithium compounds). The knowledge of the exact content of reactive species allows to better plan the required amounts for reactions preventing the waste of material or too low yields.This Application Note describes the analysis of metal organics by thermometric titration using 2-butanol as titrant. Due to the strongly exothermic nature of the reaction between 2-butanol with metal-organic compounds, a fast and quantitative analysis of these substances is possible.

Tartaric Sulfuric Anodizing (TSA) is an established technique for corrosion protection in the aerospace industry. It is an alternative to the environmentally harmful chromic anodizing process. As such, a method to monitor the levels of sulfuric acid and tartaric acid in TSA plating baths is required. Potentiometric titration methods have been developed, and are widely used across the industry. Their disadvantage is that two titrations with different electrodes and solvents are required.In this Application Note, an alternative method is presented, where the concentration of both acids is determined in sequence using a thermometric sensor. Compared to potentiometric titration, thermometric titration is faster and more convenient (no sensor maintenance required). On a fully automated system, the determination of both parameters takes about 7 minutes.

Sulfur is a secondary macronutrient for plants and is essential for chloroplast growth and function. In fertilizers, sulfur is usually provided in the form of sulfate. Traditionally the sulfate content is determined gravimetrically by precipitation with barium. The drawback of this method is that it requires numerous time consuming and laborious analysis steps.In this Application Note, an alternative method is presented, where sulfate is determined by a precipitation titration with barium chloride. Various solid and liquid NPK fertilizers with sulfur contents between 1 and 8% were analyzed. The analysis of sulfate in fertilizers by thermometric titration requires no sample preparation at all for liquid NPK fertilizers, and only minimal sample preparation for solid NPK fertilizers. One determination takes about 3 minutes only. To increase the sensitivity of the method, the samples are spiked with a standard sulfuric acid solution, which is then considered when calculating the result.

Potassium is a primary macronutrient for plants, as it plays an important role in water regulation as well as plant growth. In NPK fertilizers, potassium is present besides nitrogen and phosphorus, which are the other two primary macronutrients. Knowing the quality and content of a NPK fertilizer allows an optimal fertilizer management for a planned culture, saving costs and increasing profitability.Traditionally potassium is determined gravimetrically or by flame photometry. In this Application Note, an alternative method is presented, where potassium is determined a precipitation titration. Various solid and liquid NPK fertilizers with potassium contents between 10 and 27% were analyzed. After the removal of any present ammonia, the potassium can be determined reliably in about 5 minutes.

Cyanides are used in some industrial processes, but if not handled carefully, they could contaminate the wastewater. In an acidic or neutral environment, this contaminated wastewater can form highly toxic hydrogen cyanide gas. Furthermore, the cyanide salts could also poison the environment and enter the ground water system. Therefore, it is essential to monitor the content of cyanide in effluent water. Cyanides can be easily determined with a cyanide ion-selective electrode. This application note presents a method for cyanide analysis according to APHA Method 4500-CN and ASTM D2036.

In the synthesis of certain dyes, sodium chloride is a byproduct. The content of chloride is therefore an important parameter. This Application Note describes the determination of the chloride content in dye by standard addition using a Cl- ion-selective electrode.

As nitrogen is essential nutrient for plants, it is an essential constituent of many fertilizers. It is present there in different forms, mainly as ammonium or nitrate. Knowing the nitrogen concentration and the form in which is present helps to select the right fertilizer for the plants. For producers of fertilizers, it is therefore necessary to indicate the concentration of ammonium nitrogen in their product.This Application Note shows how to determine ammonium in liquid fertilizers by means of a standard addition.

Nitrogen is essential for plant growth. In soil, it can be present in the form of nitrate, ammonium, or urea. Knowing the nitrogen content of soil and in which form it is present helps selecting the right kind of fertilizer to stimulate plant growth.This Application Note shows a fast and reliable way to determine the ammonium concentration in soil by using standard addition.

To assess the quality of a soil it is necessary to know its nutrients. For example, it is necessary that the level of bio-available ions is known as a deficiency might negatively affect plant growth. One of the most important ions is potassiumwhich is directly absorbed in its ionic form by plants roots. It is an essential nutrient and required for proper growth and reproduction.One commonly used method to assess the K content is the extraction of phosphorous and potassium from soil with an acidic, to pH 4.1 buffered solution of calcium acetate, calcium lactate, and glacial acetic acid. This test is called calcium acetate lactate test (CAL-test). Commonly, the extract is analyzed by flame photometric method. In this application note we present a fast and inexpensive alternative using the potassium ion selective electrode.

Lucigenin is one of the most often used chemiluminescent reagents and might be used for e.g., the indication of the presence of superoxide anion radicals.Lucigenin is rather expensive to buy, however, its synthesis only includes a two stage synthesis starting from acridanone. The first stage includes an Nmethylation, the second forms the lucigenin chloride, which is finally transformed into lucigenin nitrate. To check the purity of the synthesized lucigenin, ion measurement can be applied using a nitrate selective electrode. This is a fast and inexpensive method compared to competing methods such as ion chromatography.

Increased fluoride concentrations in water may cause tooth damage, growth disorders, and bone deformation. According to the World Health Organization (WHO), concentrations above 1.5 mg/L are critical.One possible source of fluoride is landfills. Rain washes out harmful substances from landfills which can enter the groundwater. The leachate from landfills should thus be monitored for the fluoride concentration.Ion measurement is a fast and inexpensive method to determine the fluoride content in water samples compared to other methods such as ion chromatography. This Application Note describes a reproducible and accurate measurement of the fluoride content using the fluoride ion-selective electrode with an OMNIS system.

Dissolved oxygen (DO), incorporated into juices during processing, affects quality parameters of the beverage during storage such as Vitamin C concentration, color, and aroma. Various oxygen removal methods are used during juice production, such as vacuum-deaeration or gas sparging to increase product quality and extend shelf life. However, these methods have the drawback that the aroma might be affected since the volatile compounds are also removed. By assessing the DO content in fruit juices, manufacturers can improve the overall product quality. This application note describes a fast and accurate determination of dissolved oxygen in juices by using an optical sensor.

Acrylic dispersion paints are made of pigment suspended in acrylic polymer emulsions, which also include other organic material such as plasticizers, defoamers, or stabilizers. Acrylic dispersion paints are water-soluble but become resistant to water when dry. Due to the fact that once dry, acrylic dispersion paints can no longer be used, they should be stored air-tight at room temperature. For research purposes, it is of interest to assess the dissolved oxygen (DO) concentration in such samples as it is assumed that the DO amount can be related to the storage life. This Application Note describes a fast and accurate determination of dissolved oxygen by using an optical sensor.

This Application Note offers an easy way to determine the ammonia content in cacao nibs by using ion measurement, applying the standard addition technique in a reliable cost- and time-saving manner.

Determination of water content in ink is possible with Karl Fischer titration, as shown in this Application Note.

The presence of water in expandable polystyrene (EPS) can have a negative impact on the thermal insulation properties, as it increases thermal conductivity. If EPS is exposed to a high moisture environment, additional water may be absorbed, which can further affect thermal insulation.Direct analysis of the moisture content by Karl Fischer titration requires the water to be extracted from the EPS, which involves several time-consuming steps. Therefore, determination of the water content with an oven system is preferred. As EPS expands when heated, the use of sample boats, as required by ASTM D6869, is not possible, as the EPS will contaminate the oven system. This Application Note describes the determination of water content in EPS using an oven system with closed sample vials. A determination takes about 7 to 14 min depending on the water content of the sample and the sample size.

In this application note, Karl Fischer titration is used to determine the water content of urea.

This Application Note describes the determination of water content in pesticides using Karl Fischer titration.

Karl Fischer titration can be used to determine the water content in N-acetyl-L-cysteine. Special solvent mixtures can be used to prevent unwanted side reactions in the Karl Fischer titration. The water content of N-acetyl-L-cysteine can thus be determined quickly and accurately, as is shown in this Application Note.

This application note describes the water content determination in penicillin by using volumetric Karl Fischer titration. Unwanted side reactions can be avoided by using special solvent mixtures.

This Application Note describes the determination of the water content in transformer oil using the oven technique.

The water content, also called moisture content, of plastics is an important quality parameter, as it affects the properties and processability of some plastics. A high water content can lead to degradation of the plastic by hydrolysis or cause surface imperfections. Additionally, it can affect the physical properties of some plastics.For this analysis, the oven technique is used, as volatile compounds present in plastics will interfere, if the water content is directly determined by coulometric Karl Fischer titration. The water content determination in polycarbonate pellets, performed with the 885 Compact Oven Sample Changer and 899 Coulometer, is described in this Application Note.

This Application Note describes the determination of the water content in gelatine using the oven technique.

This Application Note describes the automated determination of the water content in liqueur (30% v/v) using volumetric Karl Fischer titration (MATi 10).

In this application note, Karl Fischer titration is used to determine water content in sodium acetate trihydrate. The MATi 10 allows this determination to be automated, saving users time in the laboratory.

This Application Note describes the automated determination of the water content in toothpaste using volumetric Karl Fischer titration (MATi 10).

This Application Note describes the determination of the water content in tablets using automated volumetric titration including sample preparation (MATi 11).

The bromine index indicates the degree of unsaturation and relies on the simple addition of bromine to the double bond of alkenes. One mole of bromine is consumed for each mol of carbon-carbon double bond. The bromine index indicates the olefin content in aromatic hydrocarbons. This Application Note describes the determination by coulometric titration according to ASTM D1492.

The water content determination by volumetric Karl Fischer titration is one of the most important analyses worldwide. Using an OMNIS system consisting of an OMNIS Titrator and an OMNIS Sample Robot, the fully automatic analysis of water content is possible in various products and matrices. The OMNIS Sample Robot is capable of running several different titrations in parallel. In this Application Note, we present the results of a volumetric Karl Fischer titration run in parallel to an aqueous acid-base titration on the same system. The water content is not influenced by the parallel running aqueous titration, allowing the combination of potentiometric titrations and Karl Fischer titrations on the same automated system.

The vaping and electronic cigarette industries are growing. The mixtures used in these products are usually called e-liquid, e-fluid, or e-juice. Toensure the quality of these e-liquids, testing the most important parameters is required. One important quality control parameter is water or moisture content.Water/moisture content determination by Karl Fischer titration (KFT) is an established and reliable procedure. Compared to other methods the advantages of KFT are its accuracy, speed, and selectivity. For high water content samples, such as e-liquids, volumetric KFT is the method of choice.In this Application Note a system for the fast and reliable determination of the water content in E-liquids is presented. This fully automated system performs the analysis including system preparation, blank, titer, and sample determination completely unattended. Hence, the workload of the operator is reduced to only weighing in the sample and placing the sealed sample vessels on the system.