Analytical Chemistry Laboratory, Department of Chemistry, Shivaji University, Vidyanagar, Kolhapur 416 004, Maharashtra, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2011 May;78(5):1455-66. doi: 10.1016/j.saa.2011.01.027. Epub 2011 Jan 26.
A simple and selective spectrophotometric method was developed for the determination of copper(II) with 1-(2',4'-dinitro aminophenyl)-4,4,6-trimethyl-1,4-dihydropyrimidine-2-thiol [2',4'-dinitro APTPT] as a chromogenic reagent. The procedure was based on the synergistic extraction of copper(II) with 2',4'-dinitro APTPT in the presence of 0.5 mol L(-1) pyridine to give green colored ternary complex of a molar ratio 1:2:2 (M:L:Py) in the pH range 8.7-10.5. It exhibits a maximum absorption of colored complex at 445 nm and 645 nm in chloroform against the reagent blank. Beer's law was followed in the concentration range 10-80 μg mL(-1) of copper(II) and optimum range of 20-70 μg mL(-1) the metal as evaluated from Ringbom's plot. The molar absorptivity and Sandell's sensitivity of copper(II)-2',4'-dinitro APTPT-pyridine complex in chloroform are 0.87×10(3) L mol(-1)c m(-1) and 0.072 μg cm(-2), respectively. The interfering effects of various cations and anions were also studied, and use of suitable masking agents enhances the selectivity of the method. The proposed method is rapid, reproducible and successfully applied for the determination of copper(II) in binary and synthetic mixtures, alloys, pharmaceutical formulations, environmental and fertilizer samples. Comparison of the results with those obtained using an atomic absorption spectrophotometer also tested the validity of the method.
一种简单而选择性的分光光度法被开发出来，用于测定铜(II)，其显色剂为 1-(2',4'-二硝基氨基苯基)-4,4,6-三甲基-1,4-二氢嘧啶-2-硫醇[2',4'-二硝基 APTPT]。该方法基于铜(II)与 2',4'-二硝基 APTPT 在 0.5 mol L(-1)吡啶存在下的协同萃取，在 pH 值为 8.7-10.5 的范围内生成摩尔比为 1:2:2 (M:L:Py)的绿色三元配合物。在氯仿中，与试剂空白相比，该有色配合物在 445nm 和 645nm 处有最大吸收。在 10-80μg mL(-1)的铜(II)浓度范围内和 20-70μg mL(-1)的金属浓度范围内，通过 Ringbom 图评估，符合比尔定律。铜(II)-2',4'-二硝基 APTPT-吡啶配合物在氯仿中的摩尔吸光系数和桑德尔灵敏度分别为 0.87×10(3) L mol(-1)c m(-1)和 0.072μg cm(-2)。还研究了各种阳离子和阴离子的干扰效应，并使用合适的掩蔽剂增强了方法的选择性。该方法快速、重现性好，成功应用于二元和合成混合物、合金、药物制剂、环境和肥料样品中铜(II)的测定。与原子吸收分光光度计得到的结果进行比较也验证了该方法的有效性。
