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- AN-PAN-1052Online process monitoring of octane number during catalytic reforming
In refineries, high octane products are desired since they are used to produce premium gasoline. Catalytic reforming converts heavy naphtha into a high octane liquid product called reformate (a mixture of aromatics and iso-paraffins C7 to C10). The reformate must be constantly monitored to ensure high throughput along the refining process. Traditionally, the octane numbers can be measured by two different methodologies: Inferred Octane Models (IOM) and laboratory octane engine analysis. However, these do not provide «real-time» results and require constant maintenance and human intervention to adapt to current operation conditions. «Real-time» analysis of the octane number in fuels can be performed online via near-infrared spectroscopy (NIRS) technology, which fits well within the international standards (ASTM). Utilization of a Metrohm Process Analytics NIRS XDS Process Analyzer (ATEX version) in conjunction with a sample preconditioning system makes analysis of the octane number simple, fast, and reliable, allowing quick adjustments to the process for a better quality product and higher profitability.
- AN-PAN-1048Inline moisture analysis in a pilot scale granulation process by NIRS
This Process Application Note provides a detailed account of the inline assessment of moisture during a pilot scale granulation process using a 2060 The NIR Analyzer.
- WP-067Quality control of semiconductor acid baths as per ASTM E1655 – Time- and cost-efficient with NIRS
The demand for microelectronics and printed circuit boards (PCBs) has steadily increased as more flat panel displays, LEDs, photovoltaics, and other essential intermediates are required to create modern consumer devices. This is favorable for the semiconductor industry, though challenges may arise to deliver on time while upholding high quality standards. To be successful, several processes must be optimized in order to increase production efficiency. This White Paper describes the capabilities of the modern analytical method near-infrared (NIR) spectroscopy for assessing the quality of acid baths for etching of microelectronics and printed electronics. Not only are analysis times sharply reduced to less than a minute, the related running costs are also significantly lower – certainly a boost in efficiency that should not be overlooked!
- AN-NIR-098Quality Control of PVC granulate
To monitor the quality of PVC (polyvinyl chloride), it is important to measure the molecular weight during the production process, as this parameter has a significant influence on chemical and mechanical stability as well as fire retardant properties. The standard method to determine PVC molecular weight, defined here as the average weight of the molecules that make up the polymer, is by size exclusion chromatography (SEC). This analytical method is time-intensive and requires trained personnel to perform. Determining the molecular weight of PVC is easier with near-infrared spectroscopy (NIRS). NIRS provides results in just a few seconds and can quickly indicate when adjustments to the production process are necessary.are necessary.
- AN-PAN-1060Inline process monitoring of moisture content in tetrahydrofuran
This Process Application Note presents a method to accurately monitor low levels of moisture in tetrahydrofuran (THF) in «real-time» safely, reliably, and optimally with a 2060 The NIR Analyzer from Metrohm Process Analytics. Due to the hazardous and hygroscopic nature of THF, a single explosion-proof inline process analyzer is the preferred solution for industries to reduce chemical treatment, improve product quality, and increase profits.
- AN-PAN-1055Monitoring quality parameters in standard cleaning baths
Rapid inline monitoring of the major SC1/SC2 bath constituents is possible with reagent-free near-infrared spectroscopy, e.g., the 2060 The NIR-R Analyzer.
- AN-NIR-093Quality Control of fermentation processes
The production of biofuels from renewable feedstock has grown immensely in the past several years. Bioethanol is one of the most interesting alternatives for fossil fuels, since it can be produced from raw materials rich in sugars and starch. Ethanol fermentation is one of the oldest and most important fermentation processes used in the biotechnology industry. Although the process is well-known, there is a great potential for its improvement and a proportional reduction in production costs. Due to the seasonal variation of feedstock quality, ethanol producers to need to monitor the fermentation process to ensure the same quality product is achieved. Near-infrared spectroscopy (NIRS) offers rapid and reliable prediction of ethanol content, sugars, Brix, lactic acid, pH, and total solids at any stage of the fermentation process.
- AN-NIR-109Determination of Brix, fructose, glucose, and sucrose with NIRS
Key quality parameters in the food industry include sucrose, glucose, and fructose, and Brix (dissolved sugar content). Near-infrared spectroscopy (NIRS) allows fast simultaneous determination of multiple sugars without chemicals or any sample preparation.
- AN-NIR-082Quality Control of Polypropylene
Polypropylene (PP) is a general purpose resin widely used in industries such as electronic manufacturing and construction, as well as in packaging materials. PP resins must be melted first in order to be formed into the intended shape, and therefore flow properties are important characteristics which affect the production process. The standard procedure to analyze melt flow rate (MFR) requires a significant amount of work with packing the sample, preheating, and cleaning. With no sample preparation or chemicals needed, Vis-NIR spectroscopy allows the analysis of MFR in less than a minute.
- AN-NIR-129Dried pet food analysis by near-infrared spectroscopy (NIRS)
This study shows how a pre-calibrated NIRS instrument is used for multiparameter analysis of several pet food quality indicators like protein, moisture, fat, and ash.
- AN-NIR-123Flour analysis by near-infrared spectroscopy (NIRS)
NIR spectroscopy offers fast, chemical-free analysis of ash, protein, moisture, and rheological properties in flour – ideal for routine lab or atline quality control.
- AN-NIR-041Multiparameter Quality Control of Lubricants with NIRS
For lubricant analysis, determination of the Acid Number (ASTM D664), viscosity (ASTM D445), moisture content (ASTM D6304), and color number (ASTM D1500) require the use of multiple analytical technologies and, in part, large volumes of chemicals. This application note demonstrates that the XDS RapidLiquid Analyzer operating in the visible and near-infrared spectral region (Vis-NIR) provides a fast and cost-efficient alternative for the determination of the AN, viscosity, moisture content, and color number of lubricants. With no sample preparation or chemicals needed, Vis-NIR spectroscopy allows for multi parameter analysis of lubricants in less than one minute.
- AN-RA-009Comparison of SPELEC RAMAN and standard Raman microscopes
This Application Note compares SPELEC RAMAN and a standard Raman instrument by analyzing their performance in measuring single-walled carbon nanotubes (SWCNT).
- AN-NIR-115Multiparameter quality control of palm oil with NIR spectroscopy
Near-infrared spectroscopy (NIRS) quickly assesses key quality parameters in palm oil such as iodine value and fatty acid profile without sample preparation.
- AN-NIR-116Determination of iodine value in frying oils with NIR spectroscopy
Monitoring the iodine value in edible oil blends is crucial to produce vegetable oils with the desired properties. This Application Note displays the benefit of using the Metrohm NIRS DS2500 Liquid Analyzer for quality control in food laboratories.
- AN-NIR-125Determination of olive oil quality parameters and adulteration with NIR spectroscopy
Near-infrared spectroscopy (NIRS) offers a fast, solvent-free alternative to traditional methods for assessing olive oil quality and detecting potential food fraud.
- AN-NIR-096Water in diesel with NIRS
This Application Note highlights near-infrared spectroscopy as a faster, cost-effective alternative to KF titration for predicting water content in diesel fuel.
- AN-NIR-119Moisture content and rheology determination of fluorinated polyolefins using NIRS
Near-infrared spectroscopy streamlines ethylene tetrafluoroethylene production by offering rapid, chemical-free analysis of melt flow rate and moisture content.
- AN-NIR-122Quantification of water in lactose with the OMNIS NIRS Analyzer
This Application Note shows how easy it is to determine water content in the pharmaceutical excipient lactose with reagent-free near-infrared spectroscopy.
- AN-NIR-113Research octane number (RON) determination in isomerate
The standard method to determine RON in isomerate is with expensive and maintenance-intensive engines. In contrast to this, the research octane number can also be analyzed by near-infrared spectroscopy (NIRS). NIRS provides accurate results within one minute without the need for any sample preparation or chemicals.
- AN-NIR-114Determination of RON, aromatics, benzene, olefins, and density in reformate by NIRS
The determination of key quality parameters of reformate—namely research octane number (RON, ASTM D2699-19), aromatic content (ASTM D5769-15), benzene content, olefin content, and density—requires time-consuming and laborious conventional methods. In contrast, the Metrohm DS2500 Liquid Analyzer can measure all of these parameters, providing results within one minute without any sample preparation.
- AN-NIR-099Quality Control of fermentation broths
Cell fermentation processes are a reliable production method for small molecules and protein-based active pharmaceutical ingredients (APIs). The fermentation process requires monitoring of many different parameters to ensure optimal production. These quality parameters include pH, bacterial content, potency, glucose, and concentration of reducing sugars. Traditional laboratory analysis takes a significant amount of time and requires different analytical techniques to monitor these different quality parameters. Near-infrared spectroscopy (NIRS) offers a faster and more cost-efficient alternative to traditional methods for the determination of critical parameters in fermentation broths at any stage of the fermentation process.
- AN-NIR-132Almond analysis with near-infrared (NIR) spectroscopy
This Application Note shows how NIR spectroscopy is used to determine the water content (moisture content), protein content, and fat content in whole and ground almonds.
- AN-NIR-134Paprika powder analysis with NIR spectroscopy
This study shows how NIR spectroscopy simultaneously measures capsaicin content, Scoville Heat Units, water activity, ASTA color, and ash content in paprika powder samples.
- AN-NIR-112Intrinsic viscosity (IV) determination of recycled PET by NIR spectroscopy
Near-infrared (NIR) spectroscopy is able to determine the intrinsic viscosity of rPET in less than one minute without any sample preparation. This Application Note demonstrates that the Metrohm DS2500 Solid Analyzer operating in the visible and near-infrared spectral region (Vis-NIR) offers users an easier way to perform this analysis without the use of toxic chemicals.
- AN-PAN-1053Monitoring of DOTP production via esterification with inline analysis
This Process Application Note presents a way to closely monitor multiple parameters simultaneously during the dioctyl terephthalate production process with near-infrared spectroscopy.
- AN-PAN-1062Online monitoring of sulfuric acid and hydrogen peroxide using Raman spectroscopy
Etching is a vital process in semiconductor fabrication, involving the chemical removal of layers from the wafer substrate. Strict quality control measures are necessary to determine acid etchant concentrations in mixed acid solutions (e.g., SPM, DSP, or DSP+), critical for optimizing etch rate, selectivity, and uniformity during multiple wafer etching steps. This application presents a method to measure sulfuric acid and hydrogen peroxide in etching baths simultaneously using Raman spectroscopy with the PTRam Analyzer from Metrohm Process Analytics.
- EB-004Near-infrared and Raman spectroscopy for polymer analysis: An introduction
This e-book explains how Raman and near-infrared (NIR) spectroscopy enable rapid, nondestructive polymer analysis, ensuring high quality while reducing costs and waste.
- AN-NIR-071Automated acid number determination in lubricants with near-infrared spectroscopy
Acid Number (AN) analysis of lubricants (ASTM D664) can be a lengthy and costly process due to usage of large amounts of chemicals and required cleaning steps of the analytical equipment between each measurement. This application note demonstrates that the XDS RapidLiquid Analyzer operating in the visible and near-infrared spectral region (Vis-NIR) provides a cost-efficient, fast alternative for the determination of the acid number of lubricants. With no sample preparation or chemicals needed, Vis-NIR spectroscopy allows for the analysis of AN in less than a minute.
- AN-NIR-054Quality Control of Shampoo
Determination of sodium laureth sulfate (SLES), cocamidopropyl betaine (CABP), cocamidopropylamine oxide (CAW), cocamide diethanolamine (DEA), and carbopol in shampoo is a cost- and time-intensive process due to the use of large volumes of chemicals per analysis. This application note demonstrates that the DS2500 Solid Analyzer operating in the visible and near-infrared spectral region (Vis-NIR) provides a cost-efficient and fast solution for a simultaneous determination these parameters in shampoo. With no sample preparation or chemicals needed, Vis-NIR spectroscopy allows for the complete analysis in less than a minute.
- AN-NIR-060Quality Control of Polyamides
Functional group and viscosity analysis (ASTM D789) of polyamides can be a lengthy and challenging process due to the sample’s limited solubility. This application note demonstrates that the DS2500 Solid Analyzer operating in the visible and near-infrared spectral region (Vis-NIR) provides a cost-efficient and fast solution for a simultaneous determination of the intrinsic viscosity as well as the amine, carboxylic, and moisture content in polyamides. With no sample preparation or chemicals needed, Vis-NIR spectroscopy allows for the analysis of polyamides in less than a minute.
- AN-NIR-023Quality Control of PET
Determination of the diethylene glycol content, isophthalic acid content, intrinsic viscosity (ASTM D4603), and the acid number (AN) of polyethylene terephthalate (PET) is a lengthy and challenging process due to the sample’s limited solubility and the need to use different analytical methods. This application note demonstrates that the DS2500 Solid Analyzer operating in the visible and near-infrared spectral region (Vis-NIR) provides a cost-efficient and fast solution for a simultaneous determination of these parameters in PET. Vis-NIR spectroscopy allows for the analysis of PET in less than one minute without sample preparation or using any chemical reagents.
- AN-NIR-089Quality Control of Laminates
In the semiconductor industry, thermoset resins combined with fabric or paper are used as an intermediate layer between substrates of printed circuit boards (PCB). These polymer-based sheets (laminates) are chosen depending on thickness and their thermomechanical and electrical characteristics. Near infrared spectroscopy (NIRS) is a fast, non-destructive and easy-to-use analytical method which allows the measurement of multiple key quality parameters in less than a minute. The following Application Note describes the determination of the transition time of PCB laminates by NIRS, a parameter correlating with the thickness, glass transition temperature, and tensile strength of the material.
- AN-NIR-107Quality control of Bromobutyl rubber
The synthetic rubber known as Bromobutyl (BIIR) has many of the attributes of butyl rubber, but has better adhesion to other rubbers and metals, resulting in substantially faster cure rates. The simultaneous quantification of the bromine content, Mooney viscosity, volatile content, calcium stearate content, and functional bromide in BIIR can be easily performed with near-infrared spectroscopy (NIRS) without the use of chemicals.
- AN-NIR-084Quality Control of Silicone rubber
Determination of the vinyl content of silicone rubber is a lengthy and challenging process. First, the vinyl groups must be converted to ethylene by reacting with an acid, followed by the determination of the produced ethylene with gas chromatography (GC).This application note demonstrates that Vis-NIR (visible near-infrared) spectroscopy provides a cost-efficient and fast solution for the determination of vinyl content in silicone rubbers. With the DS2500 Solid Analyzer it is possible to obtain results in less than a minute without sample preparation or any chemical reagents.
- AN-NIR-087Ethanol content in hand sanitizers
Safe and fast ethanol determination in hand sanitizers is possible with reagent-free near-infrared spectroscopy (NIRS). NIRS provides reliable results in a few seconds, quickly indicating when adjustments in formulation are necessary.
- AN-NIR-092Quality Control of PVC foils
PVC (polyvinyl chloride) foils with a PVDC (polyvinylidene chloride) coating are often used for high performance packaging films like pharmaceutical blister packs or in food packaging. In multi-layer blister films, the PVC serves as the thermoformable backbone structure, whereas the PVDC coating acts as a barrier against moisture and oxygen. The Water Vapor Transmission Rate (WVTR) and Oxygen Transmission Rate (OTR) are influenced by the composition and the thickness of the coating. A fast way to monitor PVDC coating thickness is with near-infrared spectroscopy. Results are provided in a few seconds, indicating when adjustments in the polymer production process are necessary.
- AN-PAN-1063Inline analysis of borate and sulfate solutions with Raman spectroscopy
Boric acid is growing in demand for various industrial applications, but requires a more cost-efficient and environmentally friendly production process. This Application Note describes the performance of a Raman process analyzer (PTRam) when measuring low-concentration boric acid and sodium sulfate solutions (<100 mg/L) during boric acid production.
- AN-NIR-139Quality control of ice cream mix with near-infrared spectroscopy
NIR spectroscopy measures ice cream quality parameters like total solids, fat content, lactose, protein percentage, sucrose content, and calories in seconds.
- AN-NIR-091Quality Control of Mixed Acetic, Hydrofluoric, and Nitric Acids
This application note discusses an alternative near-infrared (NIR) spectroscopy method that can reliably determine all parameters within a minute, even in complex acid mixtures.
- AN-PAN-1014Automated online determination of salt in crude oil according to ASTM D3230
Automated online analysis with the 2060 TI Ex Proof Process Analyzer facilitates constant monitoring of the crude oil desalting process according to ASTM D3230.
- AN-PAN-1031Effectively monitoring hydrogen peroxide online in salmon farms
Salmon farms are becoming ever more popular. Strong population growth increases the demand for salmon which has an effect on their cultivation. Ever more fish live in limited space in open net cages. Parasites such as salmon lice can multiply quickly due to the high density of fish. One possibility of fighting the lice is to use baths with weak concentrations of H2O2. The salmon are treated in these concentrations for up to 20 minutes until the lice fall away and die. While it is true that hydrogen peroxide decomposes relatively quickly, it is nonetheless deadly for salmon in higher concentrations. The concentration must therefore always lie within the specifications during treatment. Our process analyzer requires less than two minutes per titration. This means that it permits more concentration determinations per treatment and always guarantees the correct dosage.
- AN-NIR-128Milk powder analysis by near-infrared spectroscopy
Near-infrared spectroscopy saves time and resources by simultaneously measuring key quality parameters like lactose, moisture, fat, and protein content in milk powder.
- AN-RS-050Trace detection of mercaptans in fuel
Mercaptans in fuels are corrosive and regulated at trace levels. SERS enhances Raman signals to enable their accurate detection and quantification below standard LODs.
- AN-NIR-090Quality Control of Mixed Phosphoric, Sulfuric, Nitric, and Hydrofluoric Acids
Fast and reliable detection of phosphoric, sulfuric, nitric, and hydrofluoric acids with near-infrared spectroscopy in under one minute.
- BWT-4911Using Handheld Raman to Reduce Risks in Materials Used for Manufacturing
Raman spectroscopy is a valuable tool to provide rapid, specific analysis for identification of raw materials, thus reducing the risk of using substandard or incorrect materials in manufacturing. The utility of handheld Raman increases productivity, and the ability to do full testing without creating bottlenecks in the production process. The integration of the Raman data into a company’s data management system provides a secure means of handling data and results, with reduced risk of transcription errors, and data loss.
- AN-PAN-1026Mercaptans and hydrogen sulfide in raw oil in accordance with ASTM D3227 and UOP163
Online mercaptan and H₂S monitoring with the 2060 TI Ex Proof Analyzer certified for Zone-1 and Zone-2 areas.
- 410000016-AQuantification of Urea in Ethanol by Raman Spectroscopy
Urea in widely employed as a nitrogen-release fertilizer with more than 90 % of urea production destined for agricultural applications. Urea is also known to form complexes with fatty acids, which have been employed for separation of complex mixtures and purification processes. In this application note, we present the quantification of the concentration of urea in ethanol by Raman Spectroscopy and show how this method can be employed for determining the percentage of urea in a solid inclusion compound with stearic acid.
- AN-RS-024Trace Detection of Pyrimethanil in Wine
Pyrimethanil is a broad-spectrum fungicide. As grapevines are susceptible to fungal pathogens, large-scale viticulture operations apply pyrimethanil as part of a mixed treatment. Although chemical analysis of wines post-fermentation finds low to undetectable amounts of residue, pyrimethanil is a suspected human carcinogen. The US FDA and EU have therefore established a maximum permissible level of 5 μg/mL pyrimethanil in finished wine products.In this application, trace detection of pyrimethanil in wine with Misa (Metrohm Instant SERS Analyzer) requires few laboratory supplies and minimal sample processing, yet returns rapid results.
- AN-RS-025Trace Detection of Paraquat in Tea Leaves
Paraquat is a highly effective, yet exceptionally toxic herbicide used to manage weeds in agricultural operations. In recognition of paraquat’s danger, the EU and several other countries have banned its use for any application, though the US EPA permits its limited use by licensed applicators. Despite tight regulation, paraquat continues to be produced and is liberally used as an herbicide in over 100 countries without regulatory oversight.Testing for paraquat typically requires involved sample processing and analysis by trained chemists using expensive laboratory instruments such as HPLC, CE, and LC/MS. Misa achieves trace level detection of paraquat residue in tea leaves in a fully integrated, portable, smart system for easy on-site testing by non-technicians.
- AN-RS-020Trace Detection of Auramine O in Curry Powder
Auramine O (AO) is an industrial dye used for a broad range of manufactured products and as a fluorescent stain for detecting acid-fast bacteria in clinical specimens. Due to its intense yellow coloration, AO is also prized as an additive for enhancing the visual appeal of illicitly processed food products. Despite bans on AO as a food additive, surveillance testing indicates its persistent use as an adulterant in foods and spices.Misa (Metrohm Instant SERS Analyzer) achieves the rapid and sensitive detection of AO in curry powder in a simple assay format.
- AN-RS-026Trace Detection of Diphenylamine in Baby Food
Diphenylamine (DPA) is used as a dye fixative and antioxidant in industrial applications and as a produce preservative in agricultural operations. Food safety advocates are concerned that daily ingestion of DPA, particularly in foods meant for babies, could have negative effects on children’s health. To mitigate potentially toxic effects of DPA, both the US and EU stipulate a maximum residue limit (MRL) of 5 μg/g for whole pears and a stringent MRL of 10 ng/g for all processed baby foods.Misa (Metrohm Instant SERS Analyzer) provides a user-friendly and cost-effective alternative to traditional analytical methods used for detecting DPA in foods, such as GC-MS and GC-NPD.
- AN-PAN-1011Online analysis of permanganate absorption number (PAN)
Permanganate absorption number (PAN) analysis per ISO 8660 ensures caprolactam purity, a precursor of Nylon 6. This application describes real-time, continuous PAN monitoring.
- 410000001-CChoosing the Most Suitable Laser Wavelength For Your Raman Application
Raman instrumentation can use lasers of different laser excitation, giving the same Raman spectrum for a sample. This paper presents the specific strengths and weaknesses that different excitation wavelengths provide, allowing a user to optimize the measurement of different samples by their choice of Raman excitation laser wavelength.
- AN-RS-009Verification of fatty acids in functional foods and cosmetics
Determination of the identity and purity of ingredients is essential for the product quality of functional foods (neutraceuticals) and cosmetics. It prevents the utilization of inferior substances in the production process and thus avoids expensive delays and out-of-spec products. This Application Note describes the identification and checking of fatty acids in functional foods and cosmetics using the Metrohm Instant Raman Analyzer MIRA P.
- AN-EC-035Using a portable standalone system for easy fermentation monitoring
By using an enzymatic sensor with a screen-printed electrode, producers can measure lactic acid production, thereby monitoring fermentation processes.
- 410000046-AQTRam® for Content Uniformity Analysis of Low-Dose Pharmaceutical Tablets
In this note, we use a model drug, acetaminophen, to demonstrate the capability of QTRam® to quantify low concentrations of API in compressed tablets.QTRam® is a compact transmission Raman analyzer designed specifically for content uniformity analysis of pharmaceuticals in solid dosage forms.
- AN-RS-045Transition RMID Operations Between Handheld Raman Devices
This application shows how to seamlessly transition from Metrohm’s NanoRam 785 to the newer MIRA P system, ensuring continuity in raw material identification (RMID).
- AN-RS-039Trace Detection of Acetamiprid on Raisins
In this Application Note, MISA (Metrohm Instant SERS Analyzer) from Metrohm Raman excels in the detection of the pesticide acetamiprid on commercially sold raisins. MISA is a viable alternative to analytical laboratory testing in the quest to prevent contaminated foods from reaching and harming consumers.
- AN-RS-022Trace Detection of Carbendazim on Strawberries
Carbendazim (MBC) is a common fungicide approved for regulated use in agriculture globally, outside of the EU. Most MBC is found on fruits as surface contamination, the result of sprays applied prior to harvest. The US EPA has determined that a concentrations below 80 μg/mL in orange juice are not a health risk, while the EU restricts MBC levels to 10 ng/g (from imported produce) in foods intended for baby food production.This Application Note describes a very simple test for surface MBC and provides library spectra demonstrating the sensitive detection of MBC with Misa (Metrohm Instant SERS Analyzer).
- AN-RS-053Estimation of amine value in epoxies with Raman spectroscopy
Compared to potentiometric titration, Raman spectroscopy is a rapid, accurate, and reliable secondary method for estimating the amine value (AV) of epoxy hardeners.
- AN-RS-048Phosphates speciation with Raman spectroscopy
Metrohm’s MIRA XTR handheld Raman spectrometer enables fast, reagent-free identification of phosphate species, enabling continuous monitoring of dynamic systems.
- AN-RS-017Trace Detection of Thiabendazole on Bananas
Thiabendazole (TBZ) is a broad-spectrum pesticide used both as a fungicide in fruits and vegetables and for controlling parasites in animal feed. To ensure consumer safety, regulatory agencies establish maximum residue levels (MRL) for pesticide-treated crops based on their review of risk assessment studies. For bananas, which are either aerially sprayed or dipped in protectant solutions of TBZ, the US FDA reports a MRL of 3 μg/g, and the EU stipulates a MRL of 6 μg/g by weight.With Misa (Metrohm Instant SERS Analyzer), the rapid and sensitive detection of TBZ on bananas is demonstrated in formats easily adapted for food safety surveillance testing.
- AN-RS-027Trace Detection of Thiram on Apples
Thiram is used extensively as a fungicide and parasiticide to prevent disease in crops and as an animal repellent to protect trees and ornamental plants. However, extensive toxicological studies conclude that chronic, high-level exposure can cause considerable organ damage to land and aquatic species. The US defines maximum residue limits that vary for different food crops. In contrast, the EU recently banned thiram and is moving to use pesticides that carry reduced health risks.Using Misa (Metrohm Instant SERS Analyzer), low level detection of thiram on apples is achieved with guided workflows adapted for use by diverse testers.
- AN-RS-028SERS Detection of Brilliant Blue
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.
- 410000019-BQuantification of methanol in contaminated spirits with Raman
Methanol, often present in spirits prepared with industrial solvents like wood alcohol, can lead to blindness and even death when ingested. After an incident involving methanol-laced alcohol in the Czech Republic, they adopted Raman spectroscopy as the preferred method for identifying and quantifying methanol in contaminated spirits, following an exhaustive study using various screening tools. This Application Note discusses the reasons why Raman spectroscopy is the ideal choice for this application and shows a real-world example of Raman analysis of methanol-laced rum.
- AN-RS-056Quantification of methanol in contaminated spirits
Raman spectroscopy is ideally suited to rapidly screen for methanol contamination in spirits.
- AN-RS-023Trace Detection of Aspartame in Beverages
Some studies suggest that consumption of the artificial sweetener, aspartame, is correlated with increased risk for brain and hematopoietic cancers, however, others find it to be a safe food additive. Consequently, the US and EU approve aspartame as a multi-purpose sweetener with an acceptable daily intake of 40 mg/kg body weight/day. However, the clear health hazard to individuals suffering from phenlyketonuria and ongoing criticism by health food advocates continues to fuel the challenge against aspartame’s widespread use in the food industry.Using Misa (Metrohm Instant SERS Analyzer), beverage products are screened for aspartame levels with no sample preparation beyond simple dilution of a consumer product.
- 410000053-AQuantitative Analysis of a Water-soluble Polymer Using the i-Raman EX Spectrometer
Quantitation of the functionalization of a water-soluble polymer was achieved using a portable Raman spectrometer. The Raman spectrum provides strong, unique bands for both the initial and fully reacted polymer. This enables development of a simple, robust quantitative analysis of the percent polymer functionalization. This method is now routinely used in a manufacturing plant's quality control laboratory.
- AN-RS-019SERS Detection of Metanil Yellow in Turmeric
Metanil yellow (MY) is an azo dye used in the manufacture of external-use products such as textiles; however, it is prohibited from use as a food additive in many countries. Toxicology studies demonstrate that ingestion of MY results in significant neurological and multi-organ damage. Despite these hazards, MY is commonly used as an illicit colorant for enhancing the visual appeal of spices and legumes, most notably turmeric. Ideal tests for such food adulterants feature methods that are selective and sensitive, yet portable and convenient.Misa (Metrohm Instant SERS Analyzer) achieves rapid and accurate detection of MY in a facile assay format.
- AN-RS-021Trace Detection of Erythrosine B in Sugar
Erythrosine B (EB), also known as Red Dye #3, is a synthetic dye approved for use in candy in the US, and in pharmaceuticals and cosmetics in the EU and elsewhere. However, rodent studies suggest that ingestion of EB can promote thyroid tumor formation. EB may also be implicated as a dietary factor contributing to hyperkinesis in children. WHO recommends a daily intake of EB less than 0.1 mg/kg of body weight.The ability to obtain fast results with a portable test platform recommends Misa (Metrohm Instant SERS Analyzer) as a competitive and cost-effective alternative to laboratory technologies (e.g., CE, HPLC) currently employed for detecting EB in foodstuffs.
- 410000013-AFast and Selective Detection of Trigonelline, a Coffee Quality Marker, Using a Portable Raman Spectrometer
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.
- AN-RS-036Trace Detection of Toxic Dye in Saffron
SERS (Surface-Enhanced Raman Scattering) detection of a toxic dye (Sudan 1) used to adulterate saffron demonstrates the power of MISA (Metrohm Instant SERS Analyzer) for simple, portable food authentication in this Application Note.
- AN-RS-052Assessment of chocolate with Raman spectroscopy
Raman spectroscopy is suitable for rapid, nondestructive measurements of chocolate quality indicators (e.g., cocoa and sugar content) in various chocolate types.
- AN-RS-003Identification of conventional organic solvents with handheld Raman spectrometers
This Application Note describes the rapid and non-destructive identification of conventional organic solvents using hand-held Raman spectrometers. Measurements with the handheld Raman spectrometer Mira M-1 require no sample preparation and provide immediate and unambiguous results.
- AN-RS-049Determining phosphate concentration with Raman spectroscopy
Raman spectroscopy with PLS modeling enables rapid, accurate, nondestructive quantification of the total phosphate content in solution with minimal sample preparation.
- AN-RA-011Operando Raman characterization of oxygen evolution reaction (OER) catalysts
Operando Raman spectroelectrochemistry shows the potential-dependent structural evolution of Ni-based oxygen evolution catalysts, directly linking vibrational signatures to catalytic activity. Correlating these spectroscopic markers with electrochemical performance not only clarifies OER (oxygen evolution reaction) mechanisms but also guides the design of Ni-based catalysts for related oxidation reactions.
- AN-RS-055Low-frequency Raman spectroscopy
Low frequency Raman spectroscopy extends conventional Raman analysis by capturing vibrational modes down to 65 cm-1, enabling deeper insights into molecular structure, protein characterization, polymorph identification, and phase changes.