锌——硫酸系统新银盐法测定茶叶中痕量砷

DETERMINATION OF TRACE ARSENIC IN TEA BY A NEW ARGENTIC SALT METHOD COMBINED WITH A ZINC—SULFURIC ACID SYSTEM FOR THE GENERATION OF ARSENIC HYDRIDE

本文将锌——硫酸砷化氢发生体系同新银盐分光光度法的吸收体系相结合,进行茶叶砷含量的测定。在0～3μgAs范围内。吸光度和砷量间呈良好线性关系。方法的最低检出量为0.11μg,变异系数为6.8～8.8%,回收率为84.9～108.8%,与Ag—DDC法比较,测定结果无显著性差异。

A zinc—sulfuric acid system for the generation of arsenic hydride combined with an absorption system of a new argentic salt method was used to determine the arsenic content in tea. The linear calibration curve range was 0—3μg. The detection limit, the coefficient of variation and the recoveries of arsenic were 0.11μg, 6.8—8.8% and 84.9—108.8%, respectively. The reliability of the method was confirmed by comparision with the Ag—DDC method (t=0.428, P>0.50).