Lead determination with on-line enrichment system

The flow injection preconcentration system with a cellulose sorbent was dev eloped to determine trace; mounts of lead. The metal was preconcentrated on a microcolumn packed with Cellex P, cellulose sorbent with phosphonic acid groups, and eluted with nitric acid into the nebuliser-burner system of at omic absorption spectrometer. An enrichment factor of 47-197, equivalent of 5.1-25.5 ml of sample, was achieved by using time-based system. The detect ion limit (3 delta) for 1 min preconcentration time was 1.8 mug l(-1) and p recision (at 10 mug l(-1) level) was 7.8% (RSD). The method was applied to the determination of lead in natural water samples. (C) 2000 Elsevier Scien ce Ltd. All rights reserved.