摘要
在0.3mol.L-1KH2PO4-Na2HPO4(pH6.40)底液中,加雷沙星(Garenoxacin,简称GRX)在汞电极上有一线性扫描还原峰,峰电位EP=-1.12V(vsAg/AgCl),该峰具有明显的吸附性;吸附粒子为GRX中性分子,测得GRX在汞电极上的饱和吸附量Гs=3.92×10-11mol.cm-2,每个GRX分子所占电极面积为1.94nm2,GRX在汞电极上的吸附符合Langmuir吸附等温式;测得吸附系数β=1.14×106,25℃时的吸附自由能ΔGθ=-29.62kJ.mol-1,电极反应电子数n=2,不可逆体系动力学参量αna=1.04,表面电极反应速率常量ks=0.25s-1;建立了吸附溶出伏安法测定GRX的最佳条件,方法的检出限为2.0×10-8mol.L-1。
Abstract ： In a supporting electrolyte of 0.3mol·L^-1KH2 PO4-NaH2 PO4 （ pH6.4 ）, a reduction peak of Garenoxacin （ GRX ） with a potential of-1.12V（ vs Ag/AgCL） and adsorptive characteristics at Hg electrode was observed by linear sweep voltammetry at Hg electrode. The adsorbed species are most probably the neutral molecules of GRX. The saturaled adsorption amount of 3.92×10Y-11mol · cm^-2 and an area occupied by each molecule off. 94nm^2 at Hg electrode for GRX were obtained. On the surface of the hanging mercury drop electrode, the adsorption obeys langmuir adsorptiom isotherm. The adsorption coefficient β, the Gibbs energy of adsorption △G^8at 25 ℃, the number of electrons transferred n , the kinetic parameler an of the irreversible system αna and the rate constant k, of surface electrode reaction ka are 1.14 × 106 ,-29.62KJ · mol^-1 ,2, 1.04and 0.25s^-1, respectively. A method for the assay of GRX was proposed by adsorptive stripping vohammetry. The detection limit of the method is 2.0 × 10^-8 tool · L^-1 under the optimized conditions.
出处
《化学研究与应用》
CAS
CSCD
北大核心
2009年第2期150-154,共5页
Chemical Research and Application
基金
陕西省教育厅专项科研计划项目(06JK303)
关键词
加雷沙星
吸附溶出伏安法
电化学行为
药物分析
garenoxacin
adsorptive stripping vohammetry
electrochemical behavior
pharalaceutical analysis
