College of Chemistry, Shahrood University of Technology, Shahrood, P.O. Box 316, Iran. Gh
Spectrochim Acta A Mol Biomol Spectrosc. 2010 Jun;76(1):29-32. doi: 10.1016/j.saa.2010.02.039. Epub 2010 Mar 6.
A rapid, simple, accurate, and highly selective spectrophotometric method is proposed for the determination of periodate in water samples. This method is based on the reaction of methylene green with periodate in the presence of iodide. The decrease in the absorbance of methylene green is used to monitor the reaction spectrophotometrically at 613 nm. Under the optimum conditions, periodate could be determined in the concentration range 0.18-6.0 microg mL(-1). The detection limit for the method is 0.010 microg mL(-1). The influence of various foreign species was studied, and it was found that iodate did not interfere with the determination even in the presence of 200-fold of periodate. The relative standard deviations for six replicate determinations of 0.30, 0.50, 1.0, 1.5, 4.0, and 5.5 microg mL(-1) of periodate were 3.33, 2.0, 1.6, 1.33, 0.50, and 0.55%, respectively. The proposed method was applied to the determination of periodate in water samples and indirect determination of ethylene glycol in antifreeze and glycerol in vegetable oil via malaprade reaction, and satisfactory results were obtained.
提出了一种快速、简单、准确且高选择性的分光光度法，用于测定水样中的过碘酸盐。该方法基于甲烯蓝在碘化物存在下与过碘酸盐的反应。通过监测甲烯蓝的吸光度在 613nm 下的变化，可实现反应的分光光度法监测。在最佳条件下，过碘酸盐的浓度范围为 0.18-6.0μg mL(-1)时可被测定。该方法的检测限为 0.010μg mL(-1)。研究了各种外来物质的影响，发现即使存在 200 倍的过碘酸盐，碘酸盐也不会干扰测定。对于 0.30、0.50、1.0、1.5、4.0 和 5.5μg mL(-1)过碘酸盐的 6 次重复测定的相对标准偏差分别为 3.33、2.0、1.6、1.33、0.50 和 0.55%。该方法已应用于水样中过碘酸盐的测定以及防冻剂中乙二醇和植物油中甘油的马拉拉德反应的间接测定，获得了满意的结果。
