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Available sample size, mass sensitivity, efficiency and the detector type are important criteria in the selection of separation column dimensions. Compared to conventional 4 mm i.d. columns, microbore columns excel, above all, by their low eluent consumption. Once an eluent is prepared, it can be used for a long time. Additionally, the lower flow rates of microbore columns facilitate the hyphenation to mass spectrometers due to the improved ionization efficiency in the ion source.With the same injected sample amount, a halved column diameter involves a lower eluent flow and results in an approximate four-fold sensitivity increase. In a converse conclusion, this means that with less sample amount, microbore columns achieve the same chromatographic sensitivity and resolution than normal bore columns. This makes them ideally suited for samples of limited availability.

The Metrosep C 6 columns have a higher capacity than those of the Metrosep C 4. The present Application Note describes the exceptional separating efficiency for standard cations with the three Metrosep C 6 column lengths available. The outstanding sodium-ammonia separation is particularly noteworthy.

The Metrosep A Supp 5 microbore anion column is available in 150 and 250 mm lengths. For the two columns, the run times for separating the 7 standard anions are 20 and 29 minutes. In addition to the good separation properties and the short running times, microbore columns use approximately 75% less eluent than does their 4 mm counterpart.

The Metrosep C 4 columns are mainly used for the separation of alkali and alkaline earth metal cations including ammonium and organic amines. Additionally transition metals may be determined.

Fast IC means a high sample throughput. This is attained with short columns, relatively high flows and strong eluents. Malate, tartrate, oxalate as well as sulfate are separated within three minutes.

Fast IC means a high sample throughput. This is attained with short columns, relatively high flows and strong eluents. Here standard anions are determined within three minutes on the Metrosep A Supp 10 - 50/4.0.

Fast IC means a high sample throughput. This is attained with short columns, relatively high flows and strong eluents. Applied to drinking water analysis this means: determining chloride, nitrate and sulfate within 3 minutes.

Fast IC means short run times and a high sample throughput on columns with a relatively high flow rate and the standard eluent. Mono-, di- and trimethylamine are separated with the Metrosep C 4 - 150/2.0 within four minutes.

Fast IC means short run times and a high sample throughput on columns with a relatively high flow rate and the standard eluent. Mono-, di- and tri-ethanolamine are separated with the Metrosep C 4 - 150/2.0 within 2.5 minutes.

Fast IC means short run times and a high sample throughput. This is attained using short columns and strong eluents. Fluoride, chloride, nitrate, phosphate, sulfate and oxalate are separated in less than eight minutes using the Metrosep A Supp 5 - 100/4.0.

Fast IC means short run times and a high sample throughput. This is attained using short columns and strong eluents. Drinking water (including fluoride) is analyzed on the Metrosep A Supp 5 - 100/4.0 under the same conditions as in AN-S-322.

Fast IC means short run times on separation columns with a relatively high flow rate and the standard eluent. Here the standard cations are separated within eleven minutes on the Metrosep C 4 - 250/2.0. The sodium and ammonium peaks are separated from one another under these conditions.

Microbore columns with an inner diameter of 2 mm reduce the eluent consumption to about a quarter. Consequently, the detected peak areas of corresponding sample concentration are increased by a factor 4. In this report, the determination of anions in drinking water is described on a Metrosep A Supp 5 - 150/2.0 column.

Fast IC means short run times on separation columns with a relatively high flow rate. Separation with the Metrosep C 4 - 150/2.0 is even quicker than that in the AN-C-150 at 1.1 mL/min. Here, the standard cations are separated within five minutes. Under the selected conditions, sodium and ammonium are no longer completely separated.

Fast and handsome IC! Outstanding peak shapes on columns with the standard flow rate and a strong eluent. When the high-capacity Metrosep C 6 - 250/4.0 is used, this usually means long retention times. A strong eluent allows however the determination of the cations in drinking water in a short run time with very symmetrical peaks.

Cation analysis in drinking water is a routine task in ion chromatography and can be achieved with a variety of separating columns. The use of a microbore Metrosep C 6 - 250/2.0 column with a high eluent concentration makes it possible to reduce analysis time to less than 12 minutes. Very symmetrical peaks with high sensitivity for the divalent cations are also achieved. Direct conductivity detection is applied.

Acidic solutions used as scrubber solutions for ammonium typically have a pH of 2 or lower. This pH value is too low for silica based IC columns typically applied in direct conductivity detection of cations. The Metrosep C Supp 2 - 250/4.0 is polymer based and allows injecting low pH samples. An acidified drinking water sample spiked with ammonium is analyzed. The results indicate that such acidic solutions can be analyzed with conductivity detection after sequential cation suppression.

Metrohm's iColumns are the first IC columns that are equipped with a data chip that stores freely definable data, fixed column data as well as data entered by the MagIC NetTM software. Any relevant information such as column type, standard parameters, maximum pressure, etc. can be called up at any time. Analysis data continuously entered by the MagIC NetTM software guarantees a complete column and GLP-compliant surveillance irrespective of the IC system in which the column is operated. The MagIC NetTM software surveys the critical column data and indicates any infringement of limits.

The analytical challenge treated by the present work consists in detecting sub-ppb concentrations of low-molecular-weight amines in the presence of strongly retained cationic drugs by using ion chromatography (IC) with upstream inline coupled-column matrix elimination (CCME). In contrast to direct-injection IC, where the late elution of strongly retained drugs requires eluents with added acetonitrile, the CCME technique uses two preconcentration columns in series. In an «inverse matrix elimination step, cationic drug and target amines are trapped on a high-capacity and a very-high-capacity preconcentration column, respectively. During amine determination, a rinsing solution flushes the drug to waste. This significantly shortens the analysis time and improves sensitivity as well as selectivity. Besides the determination of monomethylamine in Nebivolol hydrochloride discussed here, the CCME technique is a promising tool for detecting further low-molecular-weight amines in a wide range of drugs.

Potassium citrate and citric acid oral solutions act as systemic alkalizers. Potassium assays, validated per USP <621> and <1225>, use IC with L76 cation-exchange columns.

The study of adverse effects of air pollution requires semi-continuous, rapid and accurate measurements of inorganic species in aerosols and their gas phase components in ambient air. The most promising instruments, often referred to as steam collecting devices, are the Particle-Into-Liquid-Sampler (PILS) coupled to wet-chemical analyzers such as a cation and/or anion chromatograph (IC) and the Monitoring instrument for AeRosols and GAses (MARGA) with two integrated ICs. Both instruments comprise gas denuders, a condensation particle growth sampler as well as pump and control devices. While PILS uses two consecutive fixed denuders and a downstream growth chamber, the MARGA system is composed of a Wet Rotating Denuder (WRD) and a Steam-Jet Aerosol Collector (SJAC). Although the aerosol samplers of PILS and MARGA use different assemblies, both apply the technique of growing aerosol particles into droplets in a supersaturated water vapor environment. Previously mixed with carrier water, the collected droplets are continuously fed into sample loops or preconcentration columns for on-line IC analysis. While PILS has been designed to sample aerosols only, MARGA additionally determines water-soluble gases. Compared to the classical denuders, which remove gases from the air sample upstream of the growth chamber, MARGA collects the gaseous species in a WRD for on-line analysis. In contrast to the gases, aerosols have low diffusion speeds and thus neither dissolve in the PILS denuders nor in the WRD. Proper selection of the ion chromatographic conditions of PILS-IC allows a precise determination, within 4 to 5 minutes, of seven major inorganic species (Na+, K+, Ca2+, Mg2+, Cl-, NO3- and SO4 2-) in fine aerosol particles. With longer analysis times (10-15 minutes) even airborne low-molecular-weight organic acids, such as acetate, formate and oxalate can be analyzed. MARGA additionally facilitates the simultaneous determination of HCl, HNO3, HNO2, SO2 and NH3.PILS and MARGA provide semi-continuous, long-term stand-alone measurements (1 week) and can measure particulate pollutants in the ng/m3 range.

Microbore ion chromatography offers better sensitivity, shorter retention times, and consumes less eluent, increasing sample throughput and reducing running costs.

Nitrite and nitrate salts are used as preservatives for meat and meat products. Nitrate salts (labeled E 251 or E 252) have a low toxicity but long-term exposure is of concern, as the lower gut reduces them to nitrite, a precursor of nitrosamines (classified as carcinogenic). Nitrite itself is classified as probably carcinogenic to humans. The European Food Safety Authority (EFSA) lists the MPL (maximum permitted levels) after the manufacturing process for nitrite (labeled E 249 or E 250) as between 50–180 mg/kg, and for nitrate between 150–300 mg/kg, depending on the product. The European Commission (Regulation (EC) No 1333/2008) limits nitrate and nitrite salts in processed meat to less than 150 mg/kg. Ion chromatography with UV detection offers a robust and universal method for quality control of nitrite and nitrate in different meat matrices. Additional sample preparation techniques like Inline Ultrafiltration help to save time and costs as well as overcome analysis issues with difficult sample matrices.

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.

Ion chromatography (IC) provides an automated, fast, and sensitive solution to accurately quantify cationic and anionic components including acetate simultaneously. This comprehensive approach makes IC an economic alternative to traditional techniques for the quality control of pharmaceutical solutions like haemodialysis concentrates. Ease-of use, accuracy, and the high-throughput of IC increase productivity and comply with the demands of modern routine and research labs.

N-Methylpyrrolidone (NMP) is crucial for lithium-ion battery production. Metrohm’s intelligent Preconcentration Technique with Matrix Elimination enables µg/L-level anion analysis in NMP.

Differentiation between Cr(III) and Cr(VI) is possible following ISO 24384 guidelines by combining ion chromatography with inductively coupled plasma mass spectrometry.

The new DIN draft standard 38407-53 outlines TFA analysis in water using direct injection LC-MS/MS, enabling quantification from 0.1–3.0 μg/L as shown in this Application Note.