Hashem Elham Y
Chemistry Department, Faculty of Science, Assiut University, Egypt.
Spectrochim Acta A Mol Biomol Spectrosc. 2002 May;58(7):1401-10. doi: 10.1016/s1386-1425(01)00590-x.
A new method for direct spectrophotometric determination of cadmium with 4-(2-pyridylazo)-resorcinol is reported. Absorption maximum, molar absorptivity and Sandell's sensitivity of the 1:1 (M:L) complex are 510 nm, 2.5 x 10(5) l mol(-1) cm(-1) and 3.55 ng cm(-2), respectively. A linear calibration graph is obtained up to 4.49 microg ml(-1). The zero-crossing measurement technique is found suitable for the direct measurement of the first-derivative value at the specified wavelengths. Cadmium(II) (0.42-9.2 microg ml(-1)) and mercury(II) (0.35-7.4 microg ml(-1)) in different ratios have been determined simultaneously. A critical evaluation of the proposed method is performed by statistical analysis of the experimental data. The developed method was applied to the simultaneous spectrophotometric determination of Cd and Hg in some synthetic mixtures and was found to give satisfactory results.
报道了一种用4-(2-吡啶偶氮)-间苯二酚直接分光光度法测定镉的新方法。1:1（金属离子:配体）配合物的最大吸收波长、摩尔吸光系数和桑德尔灵敏度分别为510 nm、2.5×10⁵ l·mol⁻¹·cm⁻¹和3.55 ng·cm⁻²。在高达4.49 μg·ml⁻¹的范围内可得到线性校准曲线。发现零交叉测量技术适用于在指定波长处直接测量一阶导数值。已同时测定了不同比例的镉(II)（0.42 - 9.2 μg·ml⁻¹）和汞(II)（0.35 - 7.4 μg·ml⁻¹）。通过对实验数据的统计分析对所提出的方法进行了严格评估。所开发的方法应用于一些合成混合物中镉和汞的同时分光光度测定，结果令人满意。
