College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei Province, PR China.
Colloids Surf B Biointerfaces. 2011 Feb 1;82(2):427-31. doi: 10.1016/j.colsurfb.2010.09.014. Epub 2010 Sep 25.
The electrochemical behavior of roxithromycin (RM) at a single-wall carbon nanotube (SWNT) coated glassy carbon (GC) electrode was studied. It was found that RM could produce an irreversible anodic peak at the electrode. When the pH of supporting electrolyte (i.e. phosphate buffer solution) was 7 the peak potential was 0.86V (vs. SCE). The electrochemical reaction contained electron and proton transfer, and the electron-transfer coefficient (α) was ca. 0.87. The anodic peak depended on the adsorption of RM, the maximum adsorption amount was about 3.99×10(-10)molcm(-2). The adsorbed RM could be removed by cycling between 0.1 and 1.1V in a blank solution for about two minutes, and the electrode thus could be regenerated. Under the optional conditions, the anodic peak current was linear to RM concentration over the range of 5.0×10(-6) to 1.0×10(-4)M. The limit of detection was 5.0×10(-7)M (S/N=3) for 180s accumulation at -0.8V. The modified electrode had good stability and repeatability, and it was successfully applied to the determination of RM in medicine samples.
罗红霉素（RM）在单壁碳纳米管（SWNT）修饰玻碳电极上的电化学行为进行了研究。结果表明，RM 在电极上产生不可逆的阳极峰。当支持电解质（即磷酸盐缓冲溶液）的 pH 值为 7 时，峰电位为 0.86V（相对于 SCE）。电化学反应包含电子和质子转移，电子转移系数（α）约为 0.87。阳极峰取决于 RM 的吸附，最大吸附量约为 3.99×10(-10)molcm(-2)。在空白溶液中，通过在 0.1 和 1.1V 之间循环约两分钟，可以去除吸附的 RM，从而使电极得以再生。在可选条件下，在 5.0×10(-6)至 1.0×10(-4)M 的范围内，阳极峰电流与 RM 浓度呈线性关系。在 -0.8V 下积累 180s 时，检测限为 5.0×10(-7)M（S/N=3）。修饰电极具有良好的稳定性和重现性，成功应用于药物样品中 RM 的测定。
