Department of Chemistry, Fudan University, Shanghai 200433, China.
Langmuir. 2010 Jun 1;26(11):9076-81. doi: 10.1021/la904630c.
The electrochemical properties of cytochrome c (cyt c) immobilized on multilayer nanozeolite-modified electrodes have been examined in aqueous and nonaqueous solutions. Layers of Linde type-L zeolites were assembled on indium tin oxide (ITO) glass electrodes followed by the adsorption of cyt c, primarily via electrostatic interactions, onto modified ITO electrodes. The heme protein displayed a quasi-reversible response in aqueous solution with a redox potential of +324 mV (vs NHE), and the surface coverage (Gamma*) increased linearly for the first four layers and then gave a nearly constant value of 200 pmol cm(-2). On immersion of the modified electrodes in 95% (v/v) nonaqueous solutions, the redox potential decreased significantly, a decrease that originated from changes in both the enthalpy and entropy of reduction. On reimmersion of the modified electrode in buffer, the faradic response immediately returned to its original value. These results demonstrate that nanozeolites are potential stable supports for redox proteins and enzymes.
细胞色素 c（cyt c）固定在多层纳米沸石修饰电极上的电化学性质已在水相和非水相溶液中进行了研究。层状 Linde 型-L 沸石组装在铟锡氧化物（ITO）玻璃电极上，然后通过静电相互作用将 cyt c 主要吸附到修饰的 ITO 电极上。该血红素蛋白在水溶液中表现出准可逆响应，氧化还原电位为+324 mV（相对于 NHE），表面覆盖率（Gamma*）在前四层呈线性增加，然后给出约 200 pmol cm(-2)的恒定值。将修饰电极浸入 95%（体积/体积）非水相溶液中后，氧化还原电位显著降低，这种降低源于还原焓和熵的变化。将修饰电极重新浸入缓冲液中后，法拉第响应立即恢复到原始值。这些结果表明，纳米沸石是氧化还原蛋白和酶的潜在稳定载体。
