利用电聚合方法在裸玻碳(GC)电极上修饰一种新型金属有机框架化合物锂均苯三甲酸(Li-BTC),并采用滴涂技术制备了Nafion/GOx/MWNTs/poly-Li-BTC/GC葡萄糖生物传感器。利用扫描电镜分析了复合膜(含MWNTs和poly-Li-BTC)的形貌,采用循环伏安和交流阻抗方法对修饰电极的电化学性能进行了研究。结果表明,此复合膜可增大裸玻碳电极的有效表面积、改善电极的电催化活性。利用循环伏安法和计时安培法研究了葡萄糖在Nafion/GOx/MWNTs/poly-Li-BTC/GC电极上的电化学特性。结果表明:葡萄糖的浓度在0.02~1.56 mmol/L范围内,此修饰电极的电流响应与葡萄糖的浓度呈线性关系,其相关系数为0.9992,检出限为5.1μmol/L(信噪比为3∶1)。修饰电极的米氏常数为0.832 mmol/L,回收率为96.3#~100.3#。本研究制备的葡萄糖生物传感器具有较好的重复性、重现性、选择性与稳定性,用于葡萄糖注射液中葡萄糖含量的检测,结果满意。
A novel organic metal framework compound-lithium 1,3,5-benzenetricarboxylic acid(Li-BTC) was polymerized on the bare glassy carbon electrode by electropolymerization method.Then,Nafion/GOx/MWNTs/poly-Li-BTC/GC electrode was fabricated by drop coating method.The morphology of the composite film containing MWNTs and poly-Li-BTC was characterized by scanning electron microscopy(SEM).The electrochemical performance of the modified electrode was investigated by cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS).The results showed the composite film increased the effective surface area and improved electrocatalytic activity of GC electrode.The electrochemical performance of Nafion/GOx/MWNTs/poly-Li-BTC/GC electrode for detection of glucose was investigated by cyclic voltammetry and chronoamperometry.The experiment results showed that the linear range for the detection of the glucose was from 0.02 to 1.56 mmol/L with a correlation coefficient of 0.9992,detection limit of 5.1 μmol/L(S/N=3 ∶ 1).The Michaelis constant was 0.832 mmol/L and recovery rate was from 96.5% to 100.3% for the modified electrode.The prepared glucose biosensor has good repeatability,reproducibility,selectivity and stability,and can be applied to determine the glucose content in glucose injection samples.