Catalysis and Nanomaterials Research Laboratory, Department of Chemistry, Loyola College, Chennai 600 034, India; Department of Chemistry, SRM Valliammai Engineering College, Chennai 603 203, India.
Catalysis and Nanomaterials Research Laboratory, Department of Chemistry, Loyola College, Chennai 600 034, India.
J Photochem Photobiol B. 2017 Apr;169:178-185. doi: 10.1016/j.jphotobiol.2017.03.013. Epub 2017 Mar 20.
In the present study, first time we report the microwave-assisted green synthesis of silver nanoparticles (AgNPs) using Tamarindus indica natural fruit extract. The plant extract plays a dual role of reducing and capping agent for the synthesis of AgNPs. The formation of spherical shape AgNPs is confirmed by XRD, HR-SEM, and HR-TEM. The presence of face-centered cubic (FCC) silver is confirmed by XRD studies and the average crystallite size of AgNPs is calculated to be around 6-8nm. The average particle diameter is found to be around 10nm, which is identified from HR-TEM images. The purity of AgNPs is confirmed by EDX analysis. The presence of sigmoid curve in UV-Visible absorption spectra suggests that the reaction has complicated kinetic features. To investigate the functional groups of the extract and their involvement in the reduction of AgNO to form AgNPs, FT-IR studies are carried out. The redox peaks are observed in cyclic voltammetry in the potential range of -1.2 to +1.2V, due to the redox active components of the T. indica fruit extract. In photoluminescence spectroscopy, the excited and emission peaks were obtained at 432nm and 487nm, respectively. The as-prepared AgNPs showed good results towards antibacterial activities. Hence, the present approach is a facile, cost- effective, reproducible, eco-friendly, and green method.
在本研究中,我们首次报道了使用罗望子天然水果提取物通过微波辅助绿色合成银纳米粒子(AgNPs)。植物提取物在 AgNPs 的合成中起到了还原和封端剂的双重作用。通过 XRD、高分辨率扫描电子显微镜(HR-SEM)和高分辨率透射电子显微镜(HR-TEM)证实了球形 AgNPs 的形成。XRD 研究证实了面心立方(FCC)银的存在,并且计算出 AgNPs 的平均晶粒尺寸约为 6-8nm。从 HR-TEM 图像中确定平均粒径约为 10nm。EDX 分析证实了 AgNPs 的纯度。紫外可见吸收光谱中的 S 形曲线表明该反应具有复杂的动力学特征。为了研究提取物中的官能团及其在将 AgNO 还原为 AgNPs 中的作用,进行了傅里叶变换红外(FT-IR)研究。在-1.2 至+1.2V 的电位范围内,循环伏安法中观察到氧化还原峰,这是由于罗望子果实提取物中的氧化还原活性成分。在光致发光光谱中,分别在 432nm 和 487nm 处获得了激发和发射峰。所制备的 AgNPs 对抗菌活性表现出良好的效果。因此,本方法是一种简便、经济有效、可重复、环保和绿色的方法。