Ion Chromatography (IC) is a specialized form of liquid chromatography in which the separation of charged molecules in solution are facilitated by a buffered mobile phase moving the sample across a polar stationary phase which interacts with the sample to separate those charged molecules by the interaction with the stationary phase. The greater the interactions, the further from the origin the separation peak will be.
The Dionex ICS-5000 is the latest in Dionex’s series in ion chromatography instruments. Capable of both cation, positively charged, and anion, negatively charged, separations. The separations are dependent on the column type and mobile phase selected. Columns are designed to be ether general purpose or specific in separation qualities.
CEST’s ICS-5000 is equipped with a conductivity detector; 147 well autosampler, 40 for 1.5-ml vials and 27 for 5-ml vials; temperature stabilization in the Autosampler, chromatography compartment and the detector compartment; and four 2 liter reservoirs for mobile phase for continuous operation).
Detection limits vary greatly depending on the specific analytes, but in general, using a general purpose column we can measure from 80 ppb (µg/L) to 100 ppm (mg/L). This range can be extended in both directions by altering the injection volume and/or the mobile phase. Commonly measured anions are fluoride, chloride, nitrite, bromide, nitrate, phosphate and sulfate but the capabilities of the hardware are not limited to these. Similarly, cations such as lithium, sodium, and magnesium can be separated and analyzed with cation specific columns and mobile phase, using the same conductivity detector as used with anion analysis.