Determination of cobalt in plant material by atomic absorption

Abstract A simple method has been developed for the determination of cobalt in plant material by atomic absorption spectrophotometry. The ashed sample was dissolved in 0.1 N‐HCl and the cobalt present chelated with ammonium pyrrolidine dithio‐carbamate. The chelate so formed was extracted and concentrated from the aqueous solution with methylisobutylketone, and this organic phase was presented to the atomic absorption spectrophotometer. Cobalt concentrations from 0 to 0.5 p.p.m. were determined. The efficiency of extraction was estimated using cobalt 60. Concomitant spectrographic analyses together with recovery experiments and replicate analyses showed that the method was suitably accurate for analysing plant material for its cobalt content in nutrition studies.