Ion Chromatography
Definition
Ion-exchange separation with conductivity detection after a suppressor, used to quantitate inorganic anions and cations such as fluoride, oxalate, sodium and calcium.
- Separation principle
- Ion-exchange resin retains charged analytes differentially
- Detection
- Conductivity detection after a suppressor column
- Typical analytes
- Fluoride, chloride, oxalate, sodium, calcium
- Common use
- Screening for corrosive or inorganic poisons
Common questions
What does the suppressor column do?+
It chemically converts the high-conductivity eluent into a low-conductivity form before the detector, so the much smaller conductivity signal from the analyte ions can be measured against a quiet background. Without it, the eluent itself would swamp the signal.
Why is ion chromatography preferred over titration for anion screening?+
A single run separates and quantifies several anions or cations at once, at lower concentrations and with less operator-dependent endpoint judgement than a manual titration, which matters when only a small forensic sample is available.
Related terms
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