Suppressed Conductivity IC
Definition
An ion chromatography detection method in which a membrane suppressor chemically neutralises the background eluent conductivity, leaving only the analyte ions as the signal source. Enables detection of inorganic anions (nitrate, sulphate, perchlorate) and cations (ammonium, potassium) at microgram-per-litre concentrations in post-blast extracts.
- Detection target
- Inorganic anions and cations in post-blast extracts
- Sensitivity level
- Microgram-per-litre (μg/L) concentrations
- Key mechanism
- Mobile phase suppression between separation and detection
Common questions
What does a suppressor membrane do in ion chromatography?+
The suppressor membrane chemically neutralises the background conductivity of the mobile phase (eluent). By removing this background noise, only the analyte ions produce a measurable electrical signal, greatly improving detection sensitivity.
What compounds can suppressed conductivity IC detect in explosives residue?+
It detects inorganic anions like nitrate, sulphate, and perchlorate, as well as cations like ammonium and potassium. These are key residues left behind after an explosion and can be found at very low concentrations in post-blast samples.
Why is suppressed conductivity the standard mode for inorganic ion analysis?+
Suppressing the background eluent conductivity dramatically improves signal-to-noise ratio, allowing reliable detection of analyte ions at microgram-per-litre concentrations. This sensitivity makes it ideal for forensic post-blast analysis where explosive residues may be present in trace amounts.
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Explained in these topics
- Laboratory Explosives Analysis: LC-MS, GC-MS, IC, XRF and SEM-EDXThe standard IC detection mode for inorganic anion/cation profiling, using a suppressor column between the separation column and the conductivity cell to neutr...
- Post-Blast Residue Sampling and the IMS, GC-ECD, LC-MS/MS WorkflowAn ion chromatography detection method in which a membrane suppressor chemically neutralises the background eluent conductivity, leaving only the analyte ions...