Preconcentration of cadmium on different sorbents in flow-injection system

The on-line solid phase extraction of trace amounts of cadmium in flow-inje ction system was developed. For preconcentration of Cd, cellulose sorbent w ith phosphonic acid groups Cellex P, chelating resin Chelex 100 and cation exchange resin Dowex 50Wx4 were investigated. The performance of these sorb ents in time-based system were compared with regard to detection limit, enr ichment factor and interferences from other metal ions. The best dynamic ch aracteristics of retention was observed for functionalized cellulose sorben t Cellex P; an enrichment factor of 260 (for 1 min sample loading) was achi eved. The detection limit (3 sigma) was 0.7 mug l(-1) and precision (at 10 mug l(-1) level) was 5.6% (RSD).