Determination of Cd in river sediment reference material by GF-ETAAS usinglithium tetraborate as chemical modifier

Lithium tetraborate was evaluated as a chemical modifier for the determinat ion of cadmium by graphite furnace electrothermal atomization atomic absorp tion spectrometry. It was found that addition of 20 mug of Li2B4O7 suffices to increase maximum pyrolysis temperature from 500 degreesC, in the absenc e of the modifier, to 800 degreesC. Pyrolysis temperature, characteristic m ass (0.35 pg), and blank values (0.013 s) were comparable to those reported for other conventional modifiers. The performance of lithium tetraborate a s a chemical modifier was evaluated for the determination of cadmium in a s tandard reference material, NIST Buffalo River Sediment (SRM 2704). The res ults (3.43 +/- 0.03) agreed well with the certified values (3.45 +/- 0.22). The detection limit of the methodology was 0.14 ng mL(-1) (n= 10).