Objective: This study aimed to establish a sensitive method for the determination of trace amount of cadmium.
Methods: The reaction systems for the generation of volatile cadmium species were investigated with vapor generation and atomic absorption spectrometry.
Results: It was found that potassium ferricyanide with hydroxylamine hydrochloride greatly enhanced the generation efficiency of the volatile species. The reaction parameters using ferricyanide-hydroxyamine-tetrahydroborate in acidic acqueous solution were optimized for efficient generation of volatile cadmium species. A detection limit (3 sigma blank, peak height mode) of 11 pg/ml was obtained under optimized conditions. The RSD of the determinations for 0.2 ngCd/ml was 3.4%. The effects of 33 diverse ions on the generation of the cadmium volatile species were investigated. The method was applied to the determination of cadmium in standard reference materials, the results obtained were in good agreement with the certified values.
Conclusion: The method can be applied to the determination of trace cadmium in environment and food samples.