School of Studies in Chemistry, Jiwaji University, Gwalior 474011, India.
Anal Biochem. 2010 Dec 1;407(1):79-88. doi: 10.1016/j.ab.2010.07.027. Epub 2010 Aug 3.
Electroreduction and adsorption of cefixime was studied in phosphate buffer by cyclic voltammetry (CV), differential pulse cathodic adsorptive stripping voltammetry (DPCAdSV), and square-wave cathodic adsorptive stripping voltammetry (SWCAdSV) at hanging mercury drop electrode (HMDE). These fully validated sensitive and reproducible cathodic adsorptive stripping voltammetric procedures were applied for the trace determination of the bulk drug in pharmaceutical formulations and in human urine. The optimal experimental parameters were as follows: accumulation potential=-0.1 V (vs. Ag/AgCl, 3M KCl), accumulation time=50s, frequency=140 Hz, pulse amplitude=0.07 V, and scan increment=10 mV in phosphate buffer (pH 2.6). The first peak current showed a linear dependence with the drug concentration over the range of 50 ng ml(-1) to 25.6 μg ml(-1). The achieved limit of detection and limit of quantitation were 3.99 and 13.3 ng ml(-1) by SWCAdSV and 7.98 and 26.6 ng ml(-1) by DPCAdSV, respectively. The procedure was applied to assay the drug in tablets. Applicability was also tested in urine samples. Peak current was linear with the drug concentration in the range of 1 to 60 μg ml(-1) of the urine, and minimum detectability was found to be 12.6 ng ml(-1) by SWCAdSV and 58.4 ng ml(-1) by DPCAdSV.
在磷酸盐缓冲液中,通过循环伏安法(CV)、差分脉冲阴极吸附溶出伏安法(DPCAdSV)和方波阴极吸附溶出伏安法(SWCAdSV)在悬汞电极(HMDE)上研究了头孢克肟的电化学还原和吸附。这些经过充分验证的灵敏且重现性好的阴极吸附溶出伏安法程序被应用于药物制剂和人尿中药物的痕量测定。最佳实验参数如下:在磷酸盐缓冲液(pH 2.6)中,累积电位为-0.1 V(相对于 Ag/AgCl,3M KCl),累积时间为 50s,频率为 140Hz,脉冲幅度为 0.07V,扫描增量为 10mV。第一峰电流在 50ngml(-1)至 25.6μgml(-1)的范围内与药物浓度呈线性关系。通过 SWCAdSV 和 DPCAdSV 获得的检测限和定量限分别为 3.99 和 13.3ngml(-1)和 7.98 和 26.6ngml(-1)。该程序用于测定片剂中的药物。还在尿液样本中测试了适用性。在 1 至 60μgml(-1)的尿液范围内,峰电流与药物浓度呈线性关系,通过 SWCAdSV 和 DPCAdSV 检测到的最低检测限分别为 12.6ngml(-1)和 58.4ngml(-1)。