以纳米金为载体,己二硫醇(HDT)为交联剂,构建了一种半网状酶标纳米金,有效地增大了酶的固定量.以此半网状酶标纳米金修饰电极构建敏感界面,用于计时电流法检测H2O2,并与无交联剂酶标纳米金构建的传感器进行比较.结果表明,半网状酶标纳米金构建的界面稳定性好,电流响应灵敏度高,能对低浓度H2O2进行准确检测,检出限达0.08μmol/L.分别用UV—Vis光谱和透射电镜对半网状酶标纳米金进行了表征.同时用电化学阻抗、石英晶体微天平及循环伏安法对此半网状修饰膜构建的界面进行了研究.
A method of producing seminetwork-type Au nanoparticles labled by horseradish peroxidase ( semi- net-nanogold-HRP) with cross-linkers 1,6-hexananedithiol(HDT) to form seminet structure to increase the immobility of HRP was developed. Compared with HRP labled Au nanoparticles without HDT, the sensitive amperometric sensor of H2O2 mediated by seminet-nanogold-HRP, which was successfully immobilized on gold electrode supported by thiol-tailed groups of HDT, was more steady with a better current response in the low H2O2 concentration, and the detection limit reaches 0.08 μmol/L. Characterization of the seminet-nanogold- HRP was carried out using UV-Vis spectroscopy and TEM. The seminet-nanogold-HRP thin film was investigated by electrochemical impedenee spectroscopy, quartz crystal microbalance and cyclic voltammograms.