Advanced Green Chemistry Lab, Department of Industrial Chemistry, School of Chemical Sciences, Alagappa University, Karaikudi 600 003, Tamil Nadu, India.
Advanced Green Chemistry Lab, Department of Industrial Chemistry, School of Chemical Sciences, Alagappa University, Karaikudi 600 003, Tamil Nadu, India.
J Photochem Photobiol B. 2017 Jun;171:117-124. doi: 10.1016/j.jphotobiol.2017.05.003. Epub 2017 May 3.
In this work, we synthesized titanium dioxide (TiO) nanoparticles using leaf extract of Morinda citrifolia (M. citrifolia) by the advanced hydrothermal method. The synthesized TiO nanoparticles were characterized by X-ray diffraction (XRD), Fourier transmission infrared (FT-IR), Ultraviolet-visible diffuse reflectance (UV-Vis DRS), Ultraviolet-visible spectroscopy (UV-Vis), Raman spectroscopy, and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM with EDX) techniques. The XRD major peak at 27.3° corresponds to the (110) lattice plane of tetragonal rutile TiO phase and average crystalline size of nanoparticles is 10nm. The FT-IR result confirmed that TiO nanoparticles and the presences of very few amount of anthraquinone and phenolic compounds of the leaf extract. The obtained nanoparticles were also characterized by UV-Vis DRS absorption spectroscopy and an intense band at 423nm clearly reveals the formation of nanoparticles. SEM images with EDX spectra clearly reveal the size of the nanoparticles, between 15 and 19nm in excellent quasi-spherical shape, by virtue of stabilization (capping) agent. The presence of elements-titanium and oxygen was verified with EDX spectrum. Furthermore, the inhibitory activity of green synthesized TiO nanoparticles was tested against human pathogens like Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, Candida albicans, and Aspergillus niger by the agar well-diffusion method. The TiO nanoparticles exhibited superior antimicrobial activity against Gram-positive bacteria, demonstrating their antimicrobial value against pathogenic diseases.
在这项工作中，我们使用余甘子（M. citrifolia）的叶提取物通过先进的水热法合成了二氧化钛（TiO）纳米粒子。合成的 TiO 纳米粒子通过 X 射线衍射（XRD）、傅里叶变换红外（FT-IR）、紫外可见漫反射（UV-Vis DRS）、紫外可见分光光度法（UV-Vis）、拉曼光谱和带有能量色散 X 射线光谱的扫描电子显微镜（SEM 与 EDX）技术进行了表征。XRD 的主要峰在 27.3°处对应于四方金红石 TiO 相的（110）晶格平面，纳米粒子的平均结晶尺寸为 10nm。FT-IR 结果证实了 TiO 纳米粒子和叶提取物中存在少量蒽醌和酚类化合物。所得纳米粒子还通过 UV-Vis DRS 吸收光谱进行了表征，在 423nm 处的强带清楚地表明了纳米粒子的形成。SEM 图像和 EDX 光谱清楚地揭示了纳米粒子的尺寸，在 15nm 至 19nm 之间，呈极好的准球形，这得益于稳定剂（封端剂）的作用。EDX 光谱证实了元素-钛和氧的存在。此外，通过琼脂孔扩散法测试了绿色合成的 TiO 纳米粒子对金黄色葡萄球菌、大肠杆菌、枯草芽孢杆菌、铜绿假单胞菌、白色念珠菌和黑曲霉等人类病原体的抑制活性。TiO 纳米粒子对革兰氏阳性菌表现出优异的抗菌活性，显示出它们对致病疾病的抗菌价值。
