Wang Yong, Ni Yong-nian
Department of Chemistry, Nanchang University, Nanchang 330047, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2008 Jun;28(6):1387-9.
A kinetic spectrophotometric method for the determination of iodate based on consecutive reactions was proposed. The method was based on the kinetic process of the analytes which react with starch-iodide in the presence of sodium chloride in sulfuric acid medium. It was found that the intermediate triiodide ion was produced in the consecutive reactions and the three peak wavelengths, 291, 354 and 585 nm, were obtained in the whole reaction process. And then the three peak wavelengths were chosen as the optimization conditions. In the reaction time of 180 s, the obtained linear calibration concentration ranges at the three peak wavelengths under the optimized conditions were 0.1-1.2, 0.05-1.2 and 0.1-1.2 microg x mL(-1), respectively, and the detection limits were 0.047, 0.027 and 0.048 microg x mL(-1), respectively. As there were the widest linear range and the lowest detection limit at the peak wavelength 354 nm, the wavelength was chosen for the quantitive ananlysis of iodate. At the same time, the method was successfully applied to the determination of iodate in iodized salt samples.
提出了一种基于连续反应测定碘酸盐的动力学分光光度法。该方法基于分析物在硫酸介质中氯化钠存在下与淀粉 - 碘化物反应的动力学过程。发现在连续反应中产生中间产物三碘离子，并且在整个反应过程中获得了291、354和585 nm三个峰值波长。然后将这三个峰值波长作为优化条件。在180 s的反应时间内，优化条件下三个峰值波长处获得的线性校准浓度范围分别为0.1 - 1.2、0.05 - 1.2和0.1 - 1.2 μg·mL⁻¹，检测限分别为0.047、0.027和0.048 μg·mL⁻¹。由于在峰值波长354 nm处具有最宽的线性范围和最低的检测限，因此选择该波长用于碘酸盐的定量分析。同时，该方法成功应用于加碘盐样品中碘酸盐的测定。
