酱油、醋中微量砷的催化示波极谱测定

Determination of Trace Arsenic in Soy and Vinegar by Catalytic Oscillopolarography

作者采用示波极谱法测定酱油、醋中的微量砷。结果表明,在2mol/L H_2SO_4-0.2mol/L KI-5μg/ml Te体系中,砷于-0.73V(甘汞电极)有一个灵敏的催化波,线性范围在0～100ppb。酱油、醋用硝酸和高氯酸消化后测定砷,其检测限达1ppb,相对标准偏差分别为4.7％、8.8％,回收率分别为92％～102％、96％～110％。

The determination of trace arsenic insoy and vinegar by oscillopolarography wasinvestigated. A sensitive catalytic wave ofarsenic appeared at -0.73Ⅴ(VS. SCE) in2mol/L H_2SO_4 -0.2 mol/L KI -5 μg/ml Tesystems. The linear relationship was 0-100ppb.The determination of arsenic in soy andvinegar was carried out after digestion withnitricperchloric acids. The detection limitwas 1 ppb.The relative standard deviationswere 4.7% and 8.8% respectively from thedeterminations of soy and vinegar.Recover-ies were 92%-102% and 96%-110% respec-tively.