【摘要】 通过Na BH4还原Ag NO3得到胶体银纳米粒子,制作了以该纳米粒子修饰的银电极,研究了其在电催化中的应用,并对相关机理进行了探讨。基于酪氨酸对纳米银的还原信号有明显抑制作用,建立了胶体银纳米粒子修饰银电极在Na Ac-HAc缓冲溶液中用差分脉冲法检测酪氨酸的方法,并讨论了优化工作条件。结果表明,在p H=5.5时,峰电流与酪氨酸的浓度在1.0×10-8~1.0×10-3mol/L范围内呈良好的线性关系,检出限为4.2×10-9mol/L,峰电流Ip与酪氨酸浓度的负对数p C的线性回归方程为Ip(μA)=7.64 p C-15.69(R=99.73%)。用该方法检测氨基酸注射液中酪氨酸的含量,加标回收率在95.2%~107.8%之间。更多还原

【Abstract】 Colloidal silver nanoparticles( Ag NPs) were prepared through reduction of Ag NO3 by Na BH4,and modified on sliver electrode surface as catalyst for several redox reactions. The mechanism of the electrocatalytic reactions was discussed. Ag NPs modified silver electrode exhibited novel electrochemical behavior, and the electrocatalytic signal of Ag NPs was obviously inhibited by added tyrosine. So a rapid and convenient voltammetric detection method for tyrosine was further established by the modified electrode,and the optimal working parameters were discussed in detail. The results showed that the peak currents have a linear relation with the concentration of tyrosine over the range from 1. 0 × 10- 8to 1. 0 × 10- 3mol / L with the detection limit of 4. 2 × 10- 9mol / L in HAcNa Ac buffer solution at p H = 5. 5. The equation of linear regression of peak current( Ip) and negative logarithm of tyrosine concentration( p C) was Ip( μA) = 7. 64 p C- 15. 69( R = 99. 53%). The response of the colloidal Ag NPs modified electrode was fast with quite reasonable reproducibility and stability. While applying it to the determination of tyrosine in amino acid injection samples,the values of recovery obtained were in the range of 95. 2% ~ 107. 8%.更多还原