【摘要】 首次制备了铁氰根和聚组氨酸(PLH)复合膜修饰电极,研究了多巴胺(DA)在该电极上的电化学行为。试验结果表明,该电极对DA的电化学氧化有显著的催化作用,在磷酸盐缓冲溶液(pH 7.6)中,多巴胺和抗坏血酸(VC)氧化峰峰电位差(ΔEp)为200 mV,从而消除了VC对DA的干扰。用示差脉冲伏安法(DPV)法测DA,线性范围为1.0×10-7~2.2×10-5mol.L-1,检出限(信噪比=3)为2.0×10-8mol.L-1。此电极于多巴胺针剂的分析,结果的RSD为3.2%。更多还原

【Abstract】 Poly-L-histidine and ferricyanide compound film modified glassy carbon electrode was prepared by electropolymerization.The electrochemical behavior of dopamine（DA） at the aboved mentioned modified electrode was studied.As shown by the experimental results,remarkable catalytic action of the modified electrode on the oxidation of DA was observed.Phosphate buffer of pH 7.6 was chosen as the base solution for the electrode reaction.Under the condition specified,the interference of ascorbic acid was effectively eliminated,since the difference of peak potentials（ΔE_p） between dopamine and ascorbic acid achieved to a value of 200 mV.Linear relationship was obtained between the oxidation peak current（I_p） of dopamine and its concentration in the range from 1.0×10^-7mol·L^-1 to 2.2×10^-5mol·L^-1.Detection limit（S/N=3） found was 2.0×10^-8mol·L^-1.In its application to the determination of DA in injections,RSD′s found were 3.2%.更多还原