制备了石墨烯/纳米金复合修饰玻碳电极,并采用扫描电子显微镜对复合膜层进行了表征,用循环伏安法和差示脉冲伏安法研究了盐酸吗啡在该修饰电极上的电化学行为。结果发现:在pH 6.8的磷酸盐缓冲溶液中,修饰电极对盐酸吗啡有良好的电催化作用,得到了一个明显的氧化峰。并在此基础上提出了一种测定盐酸吗啡的差示脉冲伏安法。盐酸吗啡的浓度在2.0×10-7~4.0×10-4mol·L-1范围内与氧化峰电流呈线性关系,检出限为7.0×10-8mol·L-1。对1.0×10-5mol·L-1盐酸吗啡标准溶液连续测定20次,测定值的相对标准偏差为3.97%。

The Graphene (GE)/nano-Au composite modified glassy carbon electrode was prepared, and the composite film was characterized by SEM. The electrochemical behavior of morphine hydrochloride at this modified electrode was studied by cyclic voltammetry and differential pulse voltammetry. Significant electrocatalytic action on the reaction of morphine hydrochloride at the modified electrode was observed, giving an oxidation peak in PBS of pH 6.8. Based on this fact, a method of differential pulse voltammetry was proposed for determination of morphine hydrochloride. Linear relationship between values of oxidation peak current and concentration of morphine hydrochloride was obtained in the range from 2.0×10-7 to 4.0×10-4mol·L-1 , with detection limit of 7.0×10-8mol·L-1. Precision of the method was tested at the concentration level of 1.0×10-5mol·L-1 morphine hydrochloride standard solution for 20 determination, value of RSD found was 3.97%.