Natural Product Chemistry Section, CSIR-North East Institute of Science and Technology, Branch Itanagar, Arunachal Pradesh 791110, India.
Colloids Surf B Biointerfaces. 2013 Feb 1;102:627-34. doi: 10.1016/j.colsurfb.2012.09.007. Epub 2012 Sep 11.
The synthesis of Ag, Au and Ag-Au bimetallic nanoparticles using Piper pedicellatum C.DC leaf extract is demonstrated here. The rapid formation of stable Ag and Au nanoparticles has been found using P. pedicellatum C.DC leaf extract in aqueous medium at normal atmospheric condition. Competitive reduction of Ag(+) and Au(3+) ions present simultaneously in solution during exposure to P. pedicellatum C.DC leaf extract leads to the synthesis of bimetallic Ag-Au nanoparticles in solution. Transmission electron microscopy (TEM) analysis revealed that the Ag nanoparticles predominantly form spherical in shape with the size range of 2.0±0.5-30.0±1.2 nm. In case of Au nanoparticles, the particles are spherical in shape along with few triangular, hexagonal and pentagonal shaped nanoparticles also observed. X-ray diffraction (XRD) studies revealed that the nanoparticles were face centered cubic (fcc) in shape. Fourier transform infrared spectroscopy (FTIR) showed nanoparticles were capped with plant compounds. The chemical constituents, viz. catechin, gallic acid, courmaric acid and protocatechuic acid of the leaf extract were identified which may act as a reducing, stabilizing and capping agent. The expected reaction mechanism in the formation of Ag and Au nanoparticles is also reported.
本文展示了使用 Piper pedicellatum C.DC 叶提取物合成 Ag、Au 和 Ag-Au 双金属纳米粒子。在正常大气条件下的水溶液中，使用 P. pedicellatum C.DC 叶提取物，快速形成了稳定的 Ag 和 Au 纳米粒子。在暴露于 P. pedicellatum C.DC 叶提取物时，溶液中同时存在的 Ag(+)和 Au(3+)离子的竞争性还原导致了溶液中双金属 Ag-Au 纳米粒子的合成。透射电子显微镜 (TEM) 分析表明，Ag 纳米粒子主要呈球形，尺寸范围为 2.0±0.5-30.0±1.2nm。对于 Au 纳米粒子，颗粒呈球形，还观察到一些三角形、六边形和五边形的颗粒。X 射线衍射 (XRD) 研究表明，纳米粒子呈面心立方 (fcc) 形状。傅里叶变换红外光谱 (FTIR) 表明纳米粒子被植物化合物覆盖。鉴定了叶提取物中的化学物质，即儿茶素、没食子酸、香豆酸和原儿茶酸，它们可能起到还原、稳定和封端的作用。还报告了形成 Ag 和 Au 纳米粒子的预期反应机制。
