How does an Ion Chromatograph (IC) work?
• A sample of the mixture to be analyzed (analyte) is injected into a carrier fluid (the eluent) • the combination is passed through a column containing a stationary fixed material (adsorbent) • Compounds contained in the analyte are then partitioned between the stationary adsorbent and the moving eluent/analyte mixture • Different dissolved materials adhere to the adsorbent with different forces • The ones that adhere strongly are moved through the adsorbent more slowly as the eluent flows over them • As the eluent flows through the column the components of the analyte will move down the column at different speeds and therefore separate from one another (Fig), (Fig) • A detector is used to analyze the output at the end of the column. There are various detectors, our IC has an electrical conductivity detector. • Each time analyte molecules/ions emerge from the chromatography column the detector generates a measurable signal which is usually printed out as a peak on the chromatogram.
