The determination of arsenic in organic and inorganic arsenic compounds: a radioisotope-dilution substoicheiometric application

Abstract

A substoicheiometric isotopic-dilution method is applied to the determination of microgram amounts of arsenic. The arsenic compound is subjected to wet acid digestion, radio-labelled with arsenic-74 standard solution, and complexed and extracted with a limiting amount of zinc diethyldithiocarbamate in chloroform. Results are given for fifty-seven determinations of nine organic compounds and sixty-eight determinations of seven inorganic compounds. Average recovery values of 99·7 ± 2·7 per cent. and 98·5 ± 2·6 per cent., respectively, are included. Exclusive of digestion time, twenty replicates of a single sample can be completed in 1 hour.