Dauthal Preeti, Mukhopadhyay Mausumi
Department of Chemical Engineering, S.V. National Institute of Technology, Surat, 395007, Gujarat, India.
3 Biotech. 2016 Dec;6(2):118. doi: 10.1007/s13205-016-0432-8. Epub 2016 Jun 2.
Biological methods of nanoparticles synthesis are ecologically sound and sustainable alternative to the conventional methods. On the basis of aforesaid premise, the present study deals with the optimization and fabrication of gold nanoparticles (Au-NPs) using easily available bio-resource, Delonix regia leaf extract. The use of practically nontoxic natural extracts and water allows the synthesis pathways presented to be considered as ''green'' and so permitting the synthesized Au-NPs to be used in sensitive areas, such as bioremediation. Various characterization techniques are adopted for the evaluation of size, stability, morphology, crystal nature, and purity of nanoparticles. Ultraviolet-visible spectroscopy analysis showed a surface Plasmon resonance peak for prepared Au-NPs at 542 nm, and its absorbance increased with increasing the interaction time. Transmission electron microscopy analysis showed that the particles were spherical and 4-24 nm in size. Energy dispersive X-ray spectroscopy analysis displayed a 2.2 keV peak corresponding to the pure phase gold nanocrystal. X-ray diffraction analysis proved the fabrication of crystalline Au-NPs with face-centered cubic geometry within 10 min. Furthermore, ζ potential (-15 mV) and Fourier transform infrared data suggested the role of polar polyphenolic compounds of leaf extract in fabrication and stabilization process. Biofabricated nanoparticles are demonstrated to have catalytic activity for the reduction of toxic nitro-organic pollutant o-nitroaniline. Therefore, the present study offers a straightforward, cost-efficient, eco-friendly, and sustainable alternative for the fabrication of catalytically active Au-NPs.
纳米颗粒合成的生物学方法是传统方法在生态上合理且可持续的替代方法。基于上述前提，本研究利用易于获取的生物资源——凤凰木叶片提取物，对金纳米颗粒（Au-NPs）进行优化和制备。使用实际无毒的天然提取物和水使得所呈现的合成途径可被视为“绿色”，从而允许将合成的金纳米颗粒用于生物修复等敏感领域。采用各种表征技术来评估纳米颗粒的尺寸、稳定性、形态、晶体性质和纯度。紫外可见光谱分析表明，制备的金纳米颗粒在542nm处有表面等离子体共振峰，其吸光度随相互作用时间的增加而增加。透射电子显微镜分析表明，颗粒呈球形，尺寸为4-24nm。能量色散X射线光谱分析显示出对应于纯相金纳米晶体的2.2keV峰。X射线衍射分析证明在10分钟内制备出了具有面心立方几何结构的晶体金纳米颗粒。此外，ζ电位（-15mV）和傅里叶变换红外数据表明叶片提取物中的极性多酚化合物在制备和稳定过程中的作用。生物制备的纳米颗粒被证明对还原有毒的硝基有机污染物邻硝基苯胺具有催化活性。因此，本研究为制备具有催化活性的金纳米颗粒提供了一种直接、经济高效、环保且可持续的替代方法。
