High Sensitive Detection Method for Anions

High Sensitive detection anion standards was performed using IC I-524A. To show the detection sensitivity, not only the sample weight but also its concentration is important. An octanesulfonate/boric acid eluent is suitable for low concentration samples because its background is low and the baseline is stable even when a large volume of sample, up to 500micro-L, is injected. Therefore, the sample concentration can be as low as micro-g/L level for the same weight sample. Standard anions of micro-g/L level concentration are injected. The minimum detection levels are shown in the table.
Figures in the parentheses are the minimum sample concentration when 500 micro-L of sample is injected.
When the pH of the eluent is larger than 4.5, phosphoric ion is detected as a negative peak.

(Preparation of eluent)
1) Put 0.195g of reagent grade sodium 1-octanesulfonate and 1.22g of reagent grade boric acid into a messflask.
2) Dilute with purified water to make up a 1 liter solution.
3) Dissolve using an ultrasonic vibrator.
4) Pass through a 0.2micro-m membrane filter before use.

Detection sensitivity
NO2-	1.0ng	(2 micro-g/L)
NO3-	1.0ng	(2 micro-g/L)
SO42-	1.5ng	(3 micro-g/L)

Please refer to 'Anion Standards (8) (Eluent : Octanesulfonic Acid and Boric Acid) '.