硅溶胶-纳米金修饰金电极电化学发光法测定苦参碱的研究

Determination of Matrine Based on Silica Sol-Nano-gold Modified Gold Electrode Using Electrochemiluminescence

基于苦参碱对联吡啶钌电化学发光的增敏作用,利用溶胶-凝胶固定化稳定的优点和纳米金对苦参碱的电催化作用,建立了硅溶胶-纳米金修饰金电极电化学发光检测苦参碱的新方法,考察了苦参碱在该修饰电极上的电化学及其发光行为。结果表明,此修饰电极表现出很好的电化学活性和电化学发光(ECL)响应,在最佳实验条件下,苦参碱浓度在1.5×10-7～1.5×10-4mol/L范围内与相对发光强度呈线性关系(r2=0.998 4),检出限(S/N=3)为7.3×10-9mol/L。连续平行测定1.5×10-5mol/L的苦参碱溶液8次,发光强度的相对标准偏差(RSDs)为1.4%。样品回收实验得到苦参碱的加标回收率为98%～102%,RSD(n=5)为1.8%。该方法具有较高的选择性和灵敏度,样品处理简单快速,用于苦参碱栓中苦参碱的测定,结果满意。

Based on the sensitization effect of matrine on Ru（bpy）2＋3 electrochemiluminescence system,an electrochemiluminescence method for the determination of matrine at silica sol-nano-gold modified gold electrode was established according to the advantages of sol-gel immobilization method and electrocatalysis of gold nanoparticles.The electrochemical and ECL characteristics of matrine at the modified electrode were studied,and the modified electrode exhibits good electrochemical activity and ECL response.Under the optimum conditions,the calibration curve was linear over matrine concentration in the range of 1.5×10-7-1.5×10-4 mol/L（r2=0.998 4）,with a detection limit（S/N=3） of 7.3×10-9 mol/L.The RSD（n=8） for determination of 1.5×10-5 mol/L matrine was 1.4%.The spiked recoveries were in the range of 98%-102%,and RSD（n=5） was 1.8%.The proposed method showed high selectivity and sensitivity,and was applied in the analysis of matrine in tablet with satisfactory results.