Determination of trace concentrations of mercury in biological materials after digestion under pressure in nitric acid catalysed by vanadium pentoxide

Abstract

The determination of trace amounts of mercury in biological materials is described. Vanadium pentoxide-catalysed digestion in nitric acid under pressure in a PTFE autoclave was used for destruction of the samples. Satisfactory destruction was achieved in the absence of sulphuric acid. Mercury was determined in the digest solution by atomic-absorption spectrophotometry using a cold vapour circulating in a closed system The detection limit was optimally 1 ng g^–1. No losses of mercury occurred. The accuracy of the determination was confirmed by the close agreement of certified and determined concentrations of mercury in reference materials.