Chen Chao, Fu Yingchun, Xiang Canhui, Xie Qingji, Zhang Qingfang, Su Yuhua, Wang Lihua, Yao Shouzhuo
Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, PR China.
Biosens Bioelectron. 2009 Apr 15;24(8):2726-9. doi: 10.1016/j.bios.2008.12.016. Epub 2008 Dec 24.
We examine here the electropolymerization of electrochemically or chemically preoxidized catecholamines in glucose oxidase (GOx)-containing neutral solutions to efficiently immobilize the enzyme at Prussian blue-modified Au electrodes for sensitive amperometric biosensing of glucose. The electrochemical quartz crystal microbalance (EQCM) was used to track various electrode-modification processes. The optimized poly(dopamine)-based glucose biosensor displayed a sensitivity of 35 microA mM(-1) cm(-2) and a limit of detection of 0.3 microM at 0.7 V vs. SCE, and similar results were obtained at -0.05 V vs. SCE, which are obviously better than those from preoxidation-free conventional electropolymerization. The immobilized GOx retained high enzymatic specific activity, as quantified by UV-vis spectrophotometry and EQCM. L-noradrenaline could similarly electropolymerize and the resultant enzyme film gave equivalent biosensing characteristics, but the electropolymerization of EP was less efficient and the resultant enzyme film showed notably poorer performance.
我们在此研究在含葡萄糖氧化酶（GOx）的中性溶液中，对经过电化学或化学预氧化的儿茶酚胺进行电聚合，以将该酶高效固定在普鲁士蓝修饰的金电极上，用于葡萄糖的灵敏安培生物传感。采用电化学石英晶体微天平（EQCM）跟踪各种电极修饰过程。优化后的基于聚多巴胺的葡萄糖生物传感器在相对于饱和甘汞电极（SCE）为0.7 V时，灵敏度为35 μA mM⁻¹ cm⁻²，检测限为0.3 μM；在相对于SCE为 -0.05 V时也获得了类似结果，这明显优于无预氧化的传统电聚合方法。通过紫外可见分光光度法和EQCM定量分析表明，固定化的GOx保留了较高的酶比活性。L - 去甲肾上腺素同样可以进行电聚合，所得酶膜具有相当的生物传感特性，但肾上腺素的电聚合效率较低，所得酶膜表现出明显较差的性能。
