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High-Performance Liquid Chromatography (HPLC) and Ion Chromatography (IC) are commonly used in the pharma, food, and environmental sectors to analyze samples for specific components and to verify compliance with norms and standards. However, users of HPLC may run into the limitations of this technique, e.g., when analyzing standard anions or certain pharmaceutical impurities. This white paper outlines how such challenges can be overcome with IC.

This article describes a simple and sensitive method for chromium(VI) determination in children's toys. The solution to be analyzed is prepared in accordance with DIN EN 71. Not only VIS detection but also post-column derivatization using diphenylcarbizide are parts of this method. The procedure described here is suitable for the precise determination of hexavalent chromium in the single-digit ppt range and, in addition, fulfils without difficulty the limit value of 10 ppt prescribed by the EU directive 2009/48/EC.

Heavy metals such as arsenic and mercury find their way into the ground water in many regions of the world, either through natural processes or as the result of human activities. Limit values are exceeded many times over, particularly for arsenic in drinking water, in many areas. This calls for a rigorous monitoring of water quality. The present whitepaper focuses on field determinations of arsenic, mercury, and copper – directly at the sampling site.

This Metrohm White Paper presents the important role of electrochemistry in the environmental sciences. The applications have to do with basic research for the fuel cell that yields energy from wastewater, the electrical clean-up of contaminated soil and electrochemical CO2 reduction of greenhouse gases for isolating chemical raw materials.

The coupling of ion chromatography and inductively coupled plasma mass spectrometry (ICP/MS) leads to a high-performance measurement system that masters several particularly challenging analyses. It enables for example reliable determination of element compositions, oxidation states and chemical bonds. This information is used, for example, for assessing the toxicity of medications, environmental and water samples as well as foods and beverages.

This White Paper focuses on selected IC-MS applications for the straightforward identification and quantification of organic acids and inorganic anions in different matrices.

The ASTM D8192 standard allows analysts to determine water hardness in different water matrices by complexometry with automated photometric endpoint recognition, increasing the reproducibility and the precision of the results.

The poster presents the ion chromatographic determination of organic degradation products such as glycolate, formate and acetate besides the standard anions fluoride, chloride, nitrate and sulfate.

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.

This poster discusses results showing the influence of pH, temperature of the post-column reactor, eluent composition, and iodide concentration on the sensitivity of the triiodide method.