Department of Applied Physics, Z. H. College of Engineering & Technology, Aligarh Muslim University, Aligarh, 202002, India.
Sci Rep. 2022 May 13;12(1):7922. doi: 10.1038/s41598-022-12081-z.
The divalent transition metal ions (Ni, Co, and Fe)-doped MgO nanoparticles were synthesized via the sol-gel method. X-ray diffraction showed the MgO pure, single cubic phase of samples at 600 °C. Field emission electron microscope showed the uniform spherical shape of samples. The magnetic behavior of Ni, Co, Fe-doped MgO system were varied with Ni, Co, Fe content (0.00, 0.01, 0.03, 0.05, 0.07). The magnetic nature of pure had changed from paramagnetic to ferromagnetic. The number of oxygen vacancies increases with increasing amounts of dopant ions that lead to an ionic charge imbalance between Ni/Co/Fe and Mg, leading to increase magnetic properties of the samples. The magnetic nature of prepared samples makes them suitable for biomedical applications. A comparative study of the antibacterial activity of nanoparticles against the Gram-negative (E. coli) and Gram-positive bacteria (S. aureus) was performed by disc diffusion, pour plate techniques, and study surface morphology of untreated and treated bacterial cell wall. An investigation of the antibacterial activity of doped MgO nanoparticles reveals that the doped MgO nanoparticles show effective antibacterial activity against the Gram-negative (E. coli) and Gram-positive (S. aureus) bacterium. The minimum inhibitory concentration of the synthesized nanoparticles against microorganisms was recorded with 40 μg/ml, while the maximum inhibitory concentration was observed with 80 μg/ml. At a concentration of 80 μg/ml, the complete growth inhibition of the E. coli was achieved with 7% Co-doped MgO and 7% Fe-doped MgO, while bacterial growth of S. aureus was inhibited by 100% in the presence of 7% Fe-doped MgO. The present work is promising for using nanomaterials as a novel antibiotic instead of the conventional antibiotics for the treatment of infectious diseases which are caused by tested bacteria.
采用溶胶-凝胶法合成了二价过渡金属离子（Ni、Co 和 Fe）掺杂的 MgO 纳米粒子。X 射线衍射表明，600°C 时样品为纯单相立方相 MgO。场发射电子显微镜显示样品呈均匀的球形。Ni、Co、Fe 掺杂 MgO 体系的磁性能随 Ni、Co、Fe 含量（0.00、0.01、0.03、0.05、0.07）而变化。纯 MgO 的磁性质从顺磁变为铁磁。随着掺杂离子数量的增加，氧空位数量增加，导致 Ni/Co/Fe 和 Mg 之间的离子电荷不平衡，从而增加了样品的磁性。制备样品的磁性使其适用于生物医学应用。通过圆盘扩散、倾倒平板技术和未处理和处理细菌细胞壁的表面形态研究，对纳米粒子对革兰氏阴性（大肠杆菌）和革兰氏阳性（金黄色葡萄球菌）细菌的抗菌活性进行了比较研究。掺杂 MgO 纳米粒子的抗菌活性研究表明，掺杂 MgO 纳米粒子对革兰氏阴性（大肠杆菌）和革兰氏阳性（金黄色葡萄球菌）细菌表现出有效的抗菌活性。合成纳米粒子对微生物的最小抑菌浓度记录为 40μg/ml，最大抑菌浓度观察到 80μg/ml。在 80μg/ml 的浓度下，7% Co 掺杂 MgO 和 7% Fe 掺杂 MgO 完全抑制了大肠杆菌的生长，而在 7% Fe 掺杂 MgO 存在的情况下，金黄色葡萄球菌的细菌生长被抑制了 100%。本工作有望将纳米材料用作新型抗生素，替代传统抗生素，用于治疗由测试细菌引起的传染病。
