石墨烯修饰玻碳电极在对苯二酚存在下选择性测定米吐尔

Graphene Modified Glassy Carbon Electrode for Selective Determination of Metol in the Presence of Hydroquinone

制备了石墨烯修饰玻碳电极(GN/GCE)。在0.5 mol/L HAc-NaAc(pH=4.8)缓冲溶液中,用循环伏安法(CV)和方波伏安法(SWV)研究了米吐尔在修饰电极上的电化学行为,建立了测定米吐尔的新方法。研究表明,米吐尔在GN/GCE上的氧化、还原峰电势差比其在裸玻碳电极(GCE)上的小,峰电流显著增加,说明GN/GCE对米吐尔有电催化作用;共存物对苯二酚干扰米吐尔的测定,通过方波伏安法可以消除其干扰。在方波伏安曲线上,米吐尔的还原峰电流与其浓度在8.0×10^(-8)~5.0×10^(-5)mol/L范围内呈线性关系,检出限为2.0×10^(-8)mol/L。该法可用于照相显影废液中米吐尔的测定。

A graphene modified glassy carbon electrode（ GN / GCE） was prepared. The electrochemical behavior of metol at the modified electrode was investigated in 0.5 mol / L HAc-Na Ac（ pH = 4.8） buffer solution by cyclic voltammetry（ CV） and square wave voltammetry（ SWV）,and a novel method for the determination of metol was established. The results show that the redox peak potential difference of metol on GN / GCE is smaller than that on the bare GCE,while the peak current is significantly increased,indicating that the GN / GCE has electrocatalytic activity toward the redox of metol. A linear dependence of the reduction current versus the metol concentration using SWV is obtained in the range of 8. 0 × 10^（-8）~ 5. 0 × 10^（- 5）mol / L,with a detection limit of 2. 0 × 10^（- 8）mol / L. The concomitant hydroquinone affects on the detection of metol,but the interference can be eliminated by using the SWV method. The proposed method can be used to determine metol in photographic imaging agents.