氮掺杂石墨烯量子点/Ru(bpy)3^2+体系电致化学发光法检测邻苯二酚

Nitrogen-Doped Graphene Quantum Dots/Ru(bpy)3^2+ Coreactant Electrochemiluminescence System and Its Application in Determination of Catechol

采用简单的方法合成了氮掺杂石墨烯量子点(NG QDs),并分别用荧光光谱仪和透射电子显微镜进行了表征。研究了NG QDs对Ru(bpy)3^2+电致化学发光(ECL)体系的增敏作用。实验优化了体系pH、Ru(bpy)3^2+用量、NG QDs用量以及扫速等条件。在最优条件下,根据邻苯二酚对NG QDs/Ru(bpy)3^2+耦合ECL体系信号的猝灭作用,建立了测定邻苯二酚的新方法。邻苯二酚浓度(1.0×10-8~1.0×10-5 mol/L)的对数值与ECL信号强度差之间呈线性关系,检测限低至5.0×10-9 mol/L,而且选择性和重现性好,实际样品检测结果令人满意。

Nitrogen-doped graphene quantum dots(NG QDs) were synthesized and characterized by fluorescence spectroscopy and transmission electron microscopy,respectively.The ECL signal of Ru(bpy)3^2+/NG QDs system was studied.The experimental conditions including the pH of electrolyte solution,the amount of Ru(bpy)3^2+,the amount of quantum dots,and the sweep rate were optimized.Under the optimal conditions,a new method for the determination of catechol has been established based on its quenching effect toward the ECL signal of NG QDs/Ru(bpy)3^2+ system.The linear relation between ECL decreased response and logarithm of catechol concentration(1.0×10-8-1.0×10-5 mol/L) with a detection limit of 5.0×10-9 mol/L was exhibited,respectively.Moreover,the results showed this method had high selectivity and reproducibility.Finally,the proposed method was used successfully for the determination of catechol in tea samples with satisfying results.