硫化镉量子点对三联吡啶钌电化学发光的增敏作用及用于邻苯二酚的检测

摘要

The effect of CdS quantum dots (QDs) on the electrochemiluminescence (ECL) signal of Ru(bpy)32+ was studied. It was found that CdS QDs could enhance the anodic ECL of Ru(bpy)32+ by 4 times. The sensitization mechanism was discussed and the influence factors including concentrations of Ru (bpy)32+ and CdS QDs, pH of solution and scan rate on ECL intensity were investigated. On the basis of quenching effect of catechol on the ECL signal of CdS QDs-Ru(bpy)32+,a system for sensitive determination of catechol was established with a detection limit of 5.5 nmol/L (S/N=3). This method was applied to the detection of catechol in tea sample with satisfactory results.%研究了CdS 量子点(CdS QDs)对三联吡啶钌(Ru(bpy)32+)电致化学发光(ECL)信号的作用,发现CdS QDs对Ru(bpy)32+的ECL信号有良好的增敏作用,基于此建立了高灵敏的CdS QDs/Ru(bpy)32+ ECL体系.探讨了该体系的ECL机理,考察了CdS QDs的浓度、缓冲溶液pH值、扫描速率等实验参数对ECL信号的影响,优化了体系的ECL条件.基于邻苯二酚对该体系ECL信号的抑制作用,建立了邻苯二酚的ECL检测方法.在1.0×10-8~1.0×10-5mol/L范围内,邻苯二酚的浓度与ECL信号的变化值呈良好的线性关系,检出限(S/N=3)为5.5 nmol/L,将本方法用于茶叶中邻苯二酚的检测,结果令人满意.