What Is Ion Chromatography Used For?
Ion chromatography is used for water chemistry analysis. Ion chromatographs are able detect and measure concentrations of major anions, such as fluoride, bromide, chloride, nitrate, nitrite, phosphate and sulfate, as well as major cations such as lithium, sodium, ammonium, potassium, calcium, and magnesium in the parts-per-billion (ppb) range. Concentrations of organic acids and amines can also be measured through ion chromatography.
How Does Ion Chromatography Work?
Ion chromatography, a form of liquid chromatography, measures concentrations of ionic species by separating them based on their interaction with a chromatographic column stationary phase. Ionic species separate differently depending on species type and size. Sample solutions pass through a pressurized chromatographic column where ions are retained by column constituents due to ionic interactions. As an ion extraction liquid, known as eluent, runs through the column, the retained ions begin separating from the column and eventually reach the detector where it produces a change in the signal which is represented by a peak in the chromatogram. Ions of interest can be identified based on their retention time and quantitated based on the detectors response to those ions.
Some typical applications of ion chromatography include:
- Drinking water analysis for pollution and other constituents
- Determination of water chemistries in aquatic ecosystems
- Analysis of residual limits in pharmaceuticals
- Determination of additives and components in foods and beverages
- Isolation of select proteins
- Trace anions in organic solvents
- Determination of ammonium, amines and other ions in industrial wastewater
- Trace ion analysis in electronics