Determination of antimony(III) and total antimony by single-drop microextraction combined with electrothermal atomic absorption spectrometry.

A simple and sensitive method for using electrothermal atomic absorption spectrometry (ET AAS) with Rh as permanent modifier determination of Sb(III) and total Sb after separation and preconcentration by N-benzoyl-N-phenylhydroxylamine (BPHA)-chloroform single drop has been developed. Parameters, such as pyrolysis and atomization temperature, solvent type, pH, BPHA concentration, extraction time, drop size, stirring rate and sample volume were investigated. Under the optimized experimental conditions, the detection limits (3sigma) were 8.0 ng L(-1) for Sb(III) and 9.2 ng L(-1) for total Sb, respectively. The relative standard deviations (R.S.Ds.) were 6.6% for Sb(III) and 7.1% for total Sb (c=0.2 ng mL(-1), n=7), respectively. The enrichment factor was 96. The developed method has been applied successfully to the determination of Sb(III) and total Sb in natural water samples.