一种新型过氧化氢传感器的构建及其在牛奶中的应用

Construction of a Novel Hydrogen Peroxide Sensor and Its Application in Milk

为构建一种新型过氧化氢生物传感器,将血红蛋白吸附在聚吡咯膜为基底的金纳米颗粒上,通过SEM、AFM、XPS、CV和EIS表征修饰电极并将该传感器用于牛奶中过氧化氢的检测。结果表明各材料成功的修饰到电极表面,且纳米金颗粒的粒径约为15 nm,Hb/AuNPs/Ppy/GCE的最佳制备条件为吡咯聚合电量3.0×10^-3 C,PBS溶液pH6.5,支持电解质溶液pH7.0。该传感器对过氧化氢的检出限为0.2μmol/L(S/N=3),检测时间12 s。此外,所构建的传感器具有良好的稳定性和选择性,金纳米颗粒大,比表面积提供更多的位点固载血红蛋白,同时血红蛋白和纳米金颗粒对过氧化氢具有良好的协同催化效果。该传感器监测牛奶中过氧化氢的加标回收率为92.7%~116.0%。结果表明,Hb/AuNPs/Ppy/GCE是一种有前途的电化学生物传感器。

In order to construct a novel hydrogen peroxide biosensor,hemoglobin was adsorbed on gold nanoparticles with polypyrrole membrane as the substrate.The modified electrodes were characterized by SEM,AFM,XPS,CV and EIS,and the sensor was used for the detection of hydrogen peroxide in milk.The results showed that materials were successfully modified to the electrode surface,and the size of the gold nanoparticles was about 15 nm.The best preparation conditions for Hb/AuNPs/Ppy/GCE were the pyrrole polymerization power 3.0×10^-3 C,the pH of PBS solution was 6.5,and the pH of supporting electrolyte solution was 7.0,the detection limit of hydrogen peroxide was 0.2μmol/L(S/N=3),and the detection time was 12 s.In addition,the constructed sensor presented good stability and selectivity,the larger specific surface area of gold nanoparticles provided more sites to immobilize hemoglobin,and the hemoglobin and gold nanoparticles possessed a good catalytic effect on hydrogen peroxide.The standard recovery rate of hydrogen peroxide in milk was 92.7%~116.0%.Those results showed that Hb/AuNPs/Ppy/GCE is a promising electrochemical biosensor.