Some Applications of Ion Chromatography

In selecting or modifying a chromatographic method, several questions need to be considered. What analytical information is truly needed. Which analyses will provide a definite answer What accuracy is required. There is no need to perform a slow, careful determination that gives a result accurate to 0.3% if a faster method accurate to 10% will suffice. Is the method selected sufficiently rugged and dependable 

There are countless situations where an ion-chromatographic determination wiU provide a fast and satisfactory answer to an analytical problem. Some of these examples may require the development of appropriate sample pretreatment or sampling techniques. For example, how does one sample fog IC determination of trace inorganic ions in very pure water often requires some form of sample preconcentration to achieve the requisite limits for quantitative detection. 

The human and economic consequences of many IC analyses are very great indeed. Thus, extremely pure water is a necessity in the manufacture of semiconductors and in the electric power industry to avoid stress corrosion of turbine blades. Food and drugs need to be free of toxic impurities. 

Let us take a closer look at the analytical needs of the pharmaceutical industry that are apt to require chromatographic determinations. Drugs must be assayed for potency and purity, and impurities must be identified and quantified. The manufacturing process often necessitates control of certain impurities. In human and animal studies, determination of drug metabolites is required. Here are a few specific applications where ion chromatography has been the method of choice. 

Analysis of counter ions in the development of small-molecule drugs which are protonated bases. These include chloride, bromide, phosphate, methanesulfonate and maleate. 

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