Mohadesi Alireza, Taher Mohammad Ali
Department of Chemistry, Shahid Bahonar University of Kerman, Kerman, Iran.
Anal Sci. 2007 Aug;23(8):969-74. doi: 10.2116/analsci.23.969.
A conducting polymer modified electrode based on the incorporation of 4,5-dihydroxy-3-(p-sulfophenylazo)-2,7-naphthalene disulfonic acid, SPADNS, as an anionic complexing ligand into polypyrrole film during electropolymerization was prepared. The electroanalysis of copper(II) in this modified electrode was achieved by medium exchange and differential pulse voltammetry. Copper ions were accumulated from ammonia buffer on the electrode surface by the formation of a chemical complex at open circuit. The resulting electrode with complexed Cu(2+) was then transferred to an acetate buffer and subjected to anodic stripping voltammetry. The analytical performance was evaluated and, finally, linear calibration graphs were obtained in the concentration range of 2 - 250 ng ml(-1) for Cu(II). The detection limit was found to be 1.1 ng ml(-1) and RSD was obtained at 3.1 and 1.9% for two different concentrations. Many coexisting metal ions had little or no effect on the determination of copper. The developed method was applied to Cu(II) determination in natural water and human hair samples. Also, the rapid and convenient regeneration of electrode allows the use of a single modified electrode in multiple analyses.
制备了一种导电聚合物修饰电极，该电极是在电聚合过程中将4,5-二羟基-3-（对磺基苯偶氮）-2,7-萘二磺酸（SPADNS）作为阴离子络合配体掺入聚吡咯膜中制成的。通过介质交换和差分脉冲伏安法实现了该修饰电极中铜（II）的电分析。在开路条件下，通过形成化学络合物，铜离子从氨缓冲液中在电极表面富集。然后将所得的络合有Cu（2+）的电极转移到乙酸盐缓冲液中，并进行阳极溶出伏安法测定。对分析性能进行了评估，最终获得了Cu（II）在2 - 250 ng ml（-1）浓度范围内的线性校准曲线。检测限为1.1 ng ml（-1），两种不同浓度下的相对标准偏差分别为3.1%和1.9%。许多共存金属离子对铜的测定影响很小或没有影响。所开发的方法应用于天然水和人发样品中Cu（II）的测定。此外，电极的快速便捷再生使得单个修饰电极可用于多次分析。
