Speciation Analysis of Trace Inorganic Arsenic in Dietary Supplements by Slurry Sampling Hydride Generation Atomic Absorption Spectrometry

Abstract

A new, rapid, and sensitive method was developed for speciation analysis of inorganic arsenic in dietary supplements using slurry sampling hydride generation atomic absorption spectrometry. As(III) content was determined under 1% HCl acidity conditions using both inhibitory effect of 8-hydroxyquinoline (8-HQ) on As(V) and its enhancing effect on As(III). Total inorganic arsenic content was determined under 5% HCl acidity conditions using the enhancing effect of 8-HQ on both As(III) and As(V). The method detection limit (S/N = 3) was 4.0 μg kg-1 for As(III) and 4.5 μg kg-1 for total inorganic arsenic. This method was validated using the Chinese standard method (GB/T 5009.11-2003), in good agreement with total inorganic arsenic content in real samples. The developed method was successfully applied to the speciation analysis of inorganic arsenic in dietary supplements with satisfactory results.