Division of Gastroenterology and Hepatology, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan.
Colloids Surf B Biointerfaces. 2012 May 1;93:169-73. doi: 10.1016/j.colsurfb.2011.12.032. Epub 2012 Jan 3.
As shown in the literature, additional energies are necessary for the reduction of positively charged noble metal ions to prepare metal nanoparticles (NPs). In this work, we report a new green pathway to prepare Au NPs in neutral 0.1M NaCl aqueous solutions from bulk Au substrates without addition of any stabilizer and reductant just via aid of natural chitosan (Ch) at room temperature. Au- and Ch-containing complexes in aqueous solution were electrochemically prepared. The role of Ch is just an intermediate to perform electron transfer with Au NPs. The stability of these prepared Au NPs is well maintained by Au NPs themselves with slightly positively charged Au remained on the surface of Au NPs. The particle size of prepared spherical Au (111) NPs is ca. 15 nm in diameter. Moreover, increasing the pH of preparation solutions can be contributive to preparing concentrated Au NPs in solutions. The prepared Au NPs are surface-enhanced Raman scattering (SERS)-active for probe molecules of Rhodamine 6G. They also demonstrate significantly catalytic activity for decomposition of acetaldehyde in rice wine.
如文献所示，为了将带正电荷的贵金属离子还原为金属纳米粒子（NPs），需要额外的能量。在这项工作中，我们报告了一种新的绿色途径，即在室温下，无需添加任何稳定剂和还原剂，仅通过天然壳聚糖（Ch）在中性 0.1M NaCl 水溶液中从块状 Au 衬底上制备 Au NPs。在水溶液中电化学制备了含 Au 和 Ch 的配合物。Ch 的作用仅仅是与 Au NPs 进行电子转移的中间物。这些制备的 Au NPs 的稳定性通过略微带正电荷的 Au 留在 Au NPs 表面上的 Au NPs 本身得到很好的保持。所制备的球形 Au（111）NPs 的粒径约为 15nm。此外，增加制备溶液的 pH 值有助于在溶液中制备浓度较高的 Au NPs。所制备的 Au NPs 对 Rhodamine 6G 等探针分子具有表面增强拉曼散射（SERS）活性。它们对米酒中乙醛的分解也表现出显著的催化活性。
