氮掺杂石墨烯基酶修饰电极测定对苯二酚

在改进的Hummers方法制备得到的氧化石墨基础上,以聚苯胺为氮源,采用水热还原法制备了氮掺杂石墨烯纳米材料,并采用傅里叶红外光谱、扫描电子显微镜等方法对制备的纳米材料进行表征。将制备的氮掺杂石墨烯与辣根过氧化物酶复合制备了酶修饰电极用来进行对苯二酚的检测。采用循环伏安法研究了该酶修饰电极对对苯二酚的催化性能。结果表明,该酶修饰电极在H_2O_2存在的情况下,对对苯二酚具有很好的催化活性,在确定的实验条件下,对苯二酚的检测线性范围为9×10~(-5)～5.075×10~(-3) mol/L,检出限为1×10~(-5) mol/L (S/N=3),灵敏度为84.14 mA/(mol·cm~2)。该酶修饰电极对尿酸、抗坏血酸、维生素E、柠檬酸、葡萄糖具有很好的抗干扰能力和选择性,同时,该酶修饰电极具有良好的重复现性,经过5次平行测定得到的相对标准偏差为2.89%。该酶修饰电极可以用于水中的对苯二酚的检测。

Nitrogen-Doped Graphene-based Enzymatically Modified Electrode for the Detection of Hydroquinone

Based on the graphite oxide produced by the improved Hummers method, nitrogen-doped graphene nanomaterials were prepared by hydrothermal reduction method using polyaniline as the nitrogen source. The prepared nanomaterials were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. Then, the prepared nitrogen-doped graphene was combined with the horseradish peroxidase to prepare an enzymatically modified electrode for the detection of hydroquinone. The catalytic performance of the modified electrode towards hydroquinone was studied by cyclic voltammetry. The results showed that in the presence of H2O2, the enzymatically modified electrode exhibited excellent catalytic activity towards hydroquinone. Under the determined experimental conditions, the linear range of detection, detection limit and sensitivity were 9 × 10-5 ~ 5.075 × 10-3 mol/L, 1 × 10-5 mol/L (S/N = 3) and 84.14 mA/(mol?cm2), respectively, with very good anti-interference ability and selectivity to uric acid, ascorbic acid, Vitamin E, citric acid and glucose. The electrode also exhibited very good reproducibility and had a relative standard deviation (RSD) of 5 measurements as 2.89% . This prepared electrode can also be used for the detection of hydroquinone in water.