Rapid analysis of ultra trace amounts of anions in water by solid phase extraction and ion chromatography

The use of solid phase extraction (SPE) technique prior to ion chromatograp hy (IC), for relative enrichment of inorganic anions is reported. The SPE i s directly coupled with the IC and comparison has been made between the det ection limits of IC, both on its own, and in combination with SPE. It has b een shown that detection limits can be reduced 100 fold using this combined technique. A number of parameters such as eluent strength, pH and flow rat e have been studied. The suppressed and non-suppressed SPE/IC have been exa mined for the analysis of aqueous samples. The suppressed SPE/IC is found t o have lower detection limits than the non-suppressed method. Recovery data and matrix dependencies have been studied at concentration levels ranging from 1 to 10 mug/l. Comparing to off line SPE method, on line SPE/IC reduce s the analysis time by at least factor of two.