Department of Physics, Mar Ivanios College, Thiruvananthapuram 695 015, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2014 Jan 24;118:793-9. doi: 10.1016/j.saa.2013.09.086. Epub 2013 Oct 8.
The use of environmentally benign procedures is highly desirable for the synthesis of nanoparticles. Here we report a simple, versatile, economic, ecofriendly and reproducible green method for the size-tunable synthesis of stable and crystalline gold nanoparticles of varied shape using aqueous extract of Garcinia Combogia fruit. The predominant anisotropic nature in the morphology of synthesized particles at lower quantities of extract gradually shifted to spherical particles with larger quantity of extract and increase of temperature. The onset of reduction, the time-evolution of the Surface Plasmon Resonance (SPR) and the catalytic activity are studied using UV-Visible spectroscopy. The Selected Area Diffraction (SAED) pattern, the lattice fringes in the High Resolution Transmission Electron Microscopic (HRTEM) image and the X-ray Diffraction (XRD) pattern clearly show the pure crystalline nature of the synthesized gold nanoparticles. The role of carboxyl group present in Garcinia Combogia fruit extract in the reduction of chloroaurate ions is established using Fourier Transform Infrared (FTIR) spectra. The size dependent catalytic activity of the green synthesized gold nanoparticles on the reduction of 4-Nitrophenol to 4-Aminophenol using sodium borohydride is studied and reported for the first time. The first order kinetics is fitted and rate constants are calculated. Catalytically active green synthesized gold nanoparticles with controllable size and shape presents an advanced step in future biomedical and chemical applications.
使用环保的程序是高度可取的合成纳米粒子。在这里，我们报道了一种简单，通用，经济，环保和可重复的绿色方法，用于使用 Garcinia Combogia 水果的水提物合成尺寸可调的稳定和结晶金纳米粒子。在较低量的提取物中，合成颗粒的形态的主要各向异性逐渐转变为具有较大量的提取物和较高温度的球形颗粒。使用紫外可见光谱研究了还原的开始，表面等离子体共振（SPR）的时间演化和催化活性。选区衍射（SAED）图案，高分辨率透射电子显微镜（HRTEM）图像中的晶格条纹和 X 射线衍射（XRD）图案清楚地表明了合成金纳米粒子的纯结晶性质。使用傅里叶变换红外（FTIR）光谱确定了 Garcinia Combogia 水果提取物中存在的羧基在氯金酸根离子还原中的作用。使用硼氢化钠研究了绿色合成金纳米粒子对 4-硝基苯酚还原为 4-氨基酚的尺寸依赖性催化活性，并首次进行了报道。拟合了一级动力学，并计算了速率常数。具有可控尺寸和形状的催化活性绿色合成金纳米粒子在未来的生物医学和化学应用中代表了一个先进的步骤。
