诺氟沙星在碳糊电极上的阴极吸附伏安法研究

Cathodic Adsorptive Voltammetric Determination of Norfloxacin at a Carbon Paste Electrode

报道了用碳糊电极阴极吸附伏安法测定诺氟沙星的方法.在B-R(pH=8.0)缓冲液中,诺氟沙星在碳糊电极(CPE)上有一灵敏的吸附还原峰,峰电位为-1.12V(vs.SCE).氧化峰的二阶导数峰电流与诺氟沙星的浓度在8.0×10-9～2.0×10-7mol/L(富集90s)范围内呈良好的线性关系,相关系数为0.9946,检出限为4.0×10-9mol/L(S/N=3,富集110s),探讨了诺氟沙星在碳糊电极上的伏安性质和电极反应机理,并且成功应用于胶囊中诺氟沙星含量的测定与回收.

A highly selective and rapid cathodic adsorptive voltammetric method was developed for the determination of trace amount of norfloxacin at a carbon paste electrode （CPE）. The norfloxacin was adsorbed on the surface of the CPE in B-R buffer solution （pH=8.0） yielding one reduction peak at -1.12 V （vs. SCE）. The relationship between the peak current and norfloxacin concentration is linear in a range of 8. 0×10^-9～2.0×10^-7mol/L with a correlation coefficient 0. 994 6. The detection limit is 4.0× 10^-9 mol/L （ S/N =3） for 110 s acummulation. The electrode reaction mechanism of norfloxacin was investigated. The proposed method was applied to direct determine trace norfloxacin in the capsules with satisfied results.