Tesfaldet Zeriet O, van Staden Jacobus F, Stefan Raluca I
Department of Chemistry, University of Pretoria, Pretoria 0002, South Africa.
Talanta. 2004 Dec 15;64(5):1213-9. doi: 10.1016/j.talanta.2004.04.038.
A simple and sensitive sequential injection spectrophotometric procedure is proposed for the determination of trace amounts of iodide in pharmaceutical preparations. The method is based on the catalytic effect of iodide on the (tetra base) 4,4'-methylenebis(N,N-dimethylaniline)-chloramine-T reaction in acidic solution. The method involves a sequential aspiration of 255mul sample/standard followed by 170mul tetra base and then 128mul chloramine-T solutions into a carrier stream to be stacked inside a holding coil and flow reversed through a reaction coil towards a detector. The resulting colored compound is measured at 600nm using an UV/Vis-spectrophotometer. All the parameters that affect the reaction were evaluated and the calibration curve is linear over a range of 0.1-6.0mugl(-1) of iodide concentration with detection limit of 0.05mugl(-1). A sample throughput of 80 samples per hour and relative standard deviation of less than 2.0% was achieved. The method is successfully applied for the determination of iodide in three different samples (tablets).
提出了一种简单灵敏的顺序注射分光光度法，用于测定药物制剂中的痕量碘化物。该方法基于碘化物在酸性溶液中对（四碱）4,4'-亚甲基双（N,N-二甲基苯胺）-氯胺-T反应的催化作用。该方法包括依次将255μl样品/标准溶液、170μl四碱溶液，然后128μl氯胺-T溶液吸入载流中，使其在保持线圈内叠加，并通过反应线圈反向流向检测器。使用紫外可见分光光度计在600nm处测量生成的有色化合物。评估了所有影响反应的参数，校准曲线在碘化物浓度为0.1-6.0μg l⁻¹范围内呈线性，检测限为0.05μg l⁻¹。实现了每小时80个样品的进样量，相对标准偏差小于2.0%。该方法成功应用于三种不同样品（片剂）中碘化物的测定。
