石墨烯纳米银的绿色合成及葡萄糖无酶电化学传感器的制备

Green Synthesis of Graphene Nano-silver and Preparation of Enzyme-free Electrochemical Sensor for Glucose

以桔皮提取液为还原剂和保护剂,通过同步还原法制得了石墨烯纳米银复合材料(RGO-AgNPs),用红外光谱法、扫描电镜法对该复合材料进行了结构与形貌表征,并用RGO-AgNPs修饰在玻碳电极上,构建了一种在低电位条件下(0 V)无酶检测葡萄糖的电化学传感器.在最佳制备条件下复合材料修饰电极对葡萄糖的催化效果非常明显.在电位为0 V时采用电流时间曲线法检测葡萄糖时,葡萄糖浓度在0.01-19 mmol/L范围内,呈现出两个线性关系,检出限为1.1×10^(-6)mol/L(S/N=3),抗坏血酸(AA)等常见干扰物质不影响葡萄糖的测定.RGO-AgNPs修饰电极连续测定1 mmol/L葡萄糖10次的相对标准偏差为1.5%,电极于冰箱保存10 d后响应电流变为初始的92.3%.实验结果表明,基于RGO-AgNPs的葡萄糖无酶传感器具有较好的选择性、重现性、稳定性.

RGO-AgNPs nanocomposites were prepared by simultaneous reduction using Orange Peel extract as reducing agent and protective agent. The structure and morphology of the composites were characterized by IR and SEM, an enzyme-free electrochemical sensor was developed for the determination of glucose at low potential(0V) using a glassy carbon electrode modified with RGO-AgNPs. Under the optimum preparation conditions, the composite modified electrode has a remarkable catalytic effect on glucose in 0.05 mol/L NaOH solution. When the potential was 0 V, the concentration of glucose was in the range of 0.01-19 mmol/L, and the detection limit was 1.1×10^(-6) mol/L(S/N = 3), common interfering substances such as ascorbic acid did not affect the determination of glucose. The RSD of RGO-AgNPs modified electrode for 1mmol/L glucose was 1.5% for 10 times, and the response current was 92.3% after 10 days in refrigerator. The results showed that the glucose sensor based on RGO-AgNPs had good selectivity, reproducibility and stability.