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):1189-95. doi: 10.1016/j.talanta.2004.02.044.
A sequential injection analysis (SIA) system is proposed for the determination of iron (II). Fe(II) was determined by SIA based on the reaction between 1,10-phenanthroline and iron (II), yielding an orange-red colour complex with absorption maximum at 512nm. The method involved aspiration of 187mul sample/standard zone followed by a zone of a reagent solution containing 140mul of 7.8 x 10(-4)moll(-1) 1,10-phenanthroline into a carrier stream to be stacked inside a holding coil and flow reversed through a reaction coil to a detector. The optimum condition was evaluated and the calibration curve is linear over a range of 0.25 to 5.0mgl(-1) of Fe(II) with detection limit of 18mugl(-1). A sample throughput of 40h(-1) was established. This technique is found to be simple, accurate, reproducible and sensitive. The proposed method was successfully applied for the determination of total iron as Fe(II) in pharmaceutical products (multi-vitamin tablets) and is especially useful for the determination of iron (II) in tablets with lower iron (II) contents. The results were found to be in good agreement with the results obtained by manual UV/Vis spectrophotometry and flame atomic absorption spectrometry (FAAS) and with claimed values by the manufacturers.
提出了一种用于测定铁（II）的顺序注射分析（SIA）系统。基于1,10 - 菲咯啉与铁（II）之间的反应，通过SIA测定铁（II），生成一种橙红色络合物，其在512nm处有最大吸收。该方法包括将187μl样品/标准区吸入，随后将含有140μl 7.8×10⁻⁴mol l⁻¹ 1,10 - 菲咯啉的试剂溶液区吸入载流中，在保持盘管内堆叠，并通过反应盘管反向流动至检测器。评估了最佳条件，校准曲线在0.25至5.0mg l⁻¹的铁（II）范围内呈线性，检测限为18μg l⁻¹。建立了每小时40个样品的分析通量。发现该技术简单、准确、可重复且灵敏。所提出的方法成功应用于药品（多种维生素片）中总铁（以铁（II）计）的测定，尤其适用于铁（II）含量较低的片剂中铁（II）的测定。结果与手动紫外/可见分光光度法和火焰原子吸收光谱法（FAAS）获得的结果以及制造商声明的值高度一致。
