Department of Chemistry and Shanghai Key Laboratory of Green Chemistry and Chemical Process, East China Normal University, 3663 Zhongshan Road (N), Shanghai, 200062, P. R. China.
Chemistry. 2011 Sep 26;17(40):11314-23. doi: 10.1002/chem.201100010. Epub 2011 Aug 18.
A series of room-temperature ionic liquids (RTILs) containing different functional groups such as hydroxyl, nitrile, carboxyl, and thiol attached to imidazolium cations, combined with various anions such as chloride [Cl], tetrafluoroborate [BF(4)], hexafluorophosphate [PF(6)], and bis[(trifluoromethyl)sulfonyl]imide [Tf(2)N], have been successfully synthesized. Dissolved in chitosan (Chi), the Chi/RTIL composites can be employed as flexible templates for the preparation of Au/Pt nanostructures. These Au/Pt nanostructures can be facilely deposited in situ on the surface of Chi/RTILs through electrodeposition. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) results demonstrate that the alloy size is significantly dependent on the structure of the Chi/RTILs, with sizes ranging from 2.8 to 84.7 nm. Based upon the functionalized RTILs, nine Chi/RTIL-Au/Pt biosensors have been fabricated. First, the size-dependent electrochemistry of Chi/RTIL-Au/Pt was investigated using potassium ferricyanide as the probe. The reversible electron transfer of the Fe(CN)(6)(3-/4-) redox couple was realized for the nine biosensors, and the peak currents, as well as the peak-to-peak separations (ΔE(p)) and electron-transfer rates, differ greatly from each other because of the diversity of the RTILs. Further electrochemical research reveals that the functional groups of these RTILs exert an evident influence on the reduction behavior of H(2)O(2), which in turn illustrates that the electrocatalytic activity of Chi/RTIL-Au/Pt nanocomposites can be tuned by means of employing RTILs with different functional groups, and an appropriate combination of cations and anions may produce a higher activity. The facilitated electron transfer and the intrinsic catalytic activity of Au/Pt NPs provide a facile way to construct a third-generation H(2)O(2) biosensor with a high sensitivity, low detection limit, quick response time, and excellent selectivity.
一系列室温离子液体（RTILs），含有不同的功能基团，如羟基、腈基、羧基和巯基连接到咪唑阳离子上，与各种阴离子，如氯 [Cl]、四氟硼酸盐 [BF(4)]、六氟磷酸盐 [PF(6)]和双[三氟甲烷磺酰基]亚胺 [Tf(2)N] 结合在一起，已成功合成。将 RTIL 溶解在壳聚糖（Chi）中，Chi/RTIL 复合材料可用作制备 Au/Pt 纳米结构的柔性模板。这些 Au/Pt 纳米结构可以通过电沉积在 Chi/RTILs 的表面上原位沉积。扫描电子显微镜（SEM）和原子力显微镜（AFM）结果表明，合金尺寸明显取决于 Chi/RTILs 的结构，尺寸范围从 2.8 到 84.7nm。基于功能化的 RTILs，制备了九种 Chi/RTIL-Au/Pt 生物传感器。首先，使用铁氰化钾作为探针研究了 Chi/RTIL-Au/Pt 的尺寸依赖性电化学。Fe(CN)(6)(3-/4-)氧化还原偶对的可逆电子转移在九个生物传感器中实现了，并且由于 RTILs 的多样性，峰电流、峰-峰分离（ΔE(p)）和电子转移速率差异很大。进一步的电化学研究表明，这些 RTILs 的功能基团对 H(2)O(2)的还原行为有明显的影响，这反过来表明，通过使用具有不同功能基团的 RTILs 可以调节 Chi/RTIL-Au/Pt 纳米复合材料的电催化活性，并且阳离子和阴离子的适当组合可能产生更高的活性。Au/Pt NPs 的促进电子转移和固有催化活性为构建具有高灵敏度、低检测限、快速响应时间和优异选择性的第三代 H(2)O(2)生物传感器提供了一种简单的方法。
