Hf-ZnO酪氨酸酶生物传感器检测邻苯二酚

Tyrosinase biosensor based on hafnium doped zinc oxide(Hf-ZnO)to detect catechol

以四氯化铪(HfCl4)和六水合硝酸锌为原料,通过水热法制得Hf掺杂氧化锌纳米材料(Hf-ZnO),并将Hf-ZnO、酪氨酸酶(Tyr)和壳聚糖(CS)修饰在玻碳电极(GCE)上,制得Tyr/Hf-ZnO/CS/GCE生物传感器。利用FESEM、DLS、XRD和XPS对Hf-ZnO的结构和性能进行表征。采用循环伏安法(CV)和计时电流法(IT)对Tyr/Hf-ZnO/CS/GCE电极进行电化学测试。结果表明,Tyr/Hf-ZnO/CS/GCE电极在pH=5和–50 mV的低电势下对邻苯二酚有最佳检测能力,对邻苯二酚检测的线性范围是0.5~47.0μmol/L,灵敏度为195 mA/(mol/L),检测限是0.1215μmol/L(S/N=3)。此外,该生物电极的稳定性和重复性较好,可有效避免尿素、多巴胺、抗坏血酸等与邻苯二酚电化学活性相近物质的干扰。

A series of hafnium doped zinc oxide(Hf-ZnO)nano particles were prepared from tetrachloride hafnium(HfCl4)and zinc nitrate by hydrothermal method.An electrochemical biosensor of Tyr/Hf-ZnO/CS/GCE was obtained by modifying tyrosinase(Tyr),Hf-ZnO and chitosan(CS)onto glassy carbon electrode(GCE).The structure and properties of Hf-ZnO were characterized by FESEM,DLS,XRD and XPS.Electrochemical performances of Tyr/Hf-ZnO/CS/GCE were tested by cyclic voltammetry(CV)and chronoamperometry(IT).The results showed that Tyr/Hf-ZnO/CS/GCE electrode had the best detection ability for catechol at a low potential of–50 mV and at pH 5.The linear range of catechol detection was 0.5~47.0μmol/L,the sensitivity was 195 mA/(mol/L),and the detection limit was 0.1215μmol/L(S/N=3).In addition,the biological electrode had good stability and repeatability,and could effectively avoid the interference of substances similar to the electrical activity of catechol such as urea,dopamine,ascorbic acid.