酶法合成的葡萄糖氧化酶-纳米金复合物的直接电化学与生物传感

将NaAuCl₄、葡萄糖氧化酶（GOx）和葡萄糖混合，借一步酶促反应制得吸附GOx的金纳米颗粒（AuNPs），再通过滴干修饰法研制了Nafion/GOx-AuNPs修饰的玻碳（GC）电极，并考察了该酶电极上GOx的直接电化学和生物传感性能. 这种酶法合成的GOx-AuNPs复合物有良好的酶直接电化学活性，也保持了GOx的生物活性，似可归因于酶法合成的纳米金更接近酶氧化还原活性中心的缘故. 该酶电极在-0.4 V（vs. SCE）电位下，其稳态电流下降与葡萄糖浓度（0.5 4 mmol·L^-1）成正比，检测下限0.2 mol·L^-1.

Direct Electrochemistry and Glucose Biosensing of Glucose Oxidase-Gold Nanoparticles Composite Synthesized by Enzyme Method

Glucose oxidase (GOx)-gold nanoparticles (AuNPs) composite was synthesized by the one-pot enzyme reaction in the mixture solution of NaAuCl₄, GOx and glucose, and a Nafion/GOx-AuNPs/glassy carbon electrode was fabricated by the cast-coating method to examine the direct electrochemistry of GOx and the biosensing performance on this electrode. Such a GOx-AuNPs composite showed good direct-electrochemistry activity and bioactivity of GOx, probably because the enzyme-mediated AuNPs are close to the redox active centers of GOx. This enzyme electrode exhibited a linear amperometric response to glucose concentration (0.54 mmol·L^-1) at -0.4 V (vs. SCE), and a detection limit of 0.2 mol·L^-1 was obtained.