1. Laboratory for Conservation and Utilization of Bio-Resource & School of Life Science, Yunnan University, Kunming 650091, China 2. Department of Basic Courses, Southwestern Forestry College, Kunming 650224, China 3. Supervision and Testing Center for Farm Products Quality，Ministry of Agriculture，Kunming 650000, China
Abstract：A highly sensitive, selective and rapid method for the determination of zinc based on the rapid reaction of zinc(Ⅱ) with 2-(2-quinolylazo)-5-dimthylaminophenol (QADMAP) and the solid phase extraction of zinc ion with anion exchange resin cartridge was developed. In the presence of pH 8.5 buffer solution and Triton X-100 medium, QADMAP can react with zinc(Ⅱ) to form a stable 2∶1 complex (QADMAP∶Zn(Ⅱ)). The molar absorptivity is 1.22×105 L·moL-1·cm-1 at 590 nm. Beer’s law is obeyed in the range of 0-1.0 μg·mL-1. The zinc ions in the samples can be enriched and separated by solid phase extraction with anion exchange resin cartridge. Testing results show that recovery for zinc(Ⅱ) was from 95% to 104%, and RSD was below 3%. This method was applied to the determination of zinc in water and food with good results.
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