El-Khawaga Ahmed M, Elsaidy Amir, Correa-Duarte Miguel A, Elbasuney Sherif
Department of Basic Medical Sciences, Faculty of Medicine, Galala University, New Galala City, Suez, Egypt.
School of Chemical engineering, Military Technical College, Cairo, Egypt.
Sci Rep. 2025 Jan 7;15(1):1201. doi: 10.1038/s41598-024-82332-8.
This study reports on the facile development of star-shaped gold nanoparticles via seed-mediated growth protocol. Gold nanostars (AuNSTs) demonstrated average particle size of 48 nm using transmission electron microscopy (TEM). Chemical composition of AuNSTs was verifired using energy dispersive X-ray spectroscopy (EDX) mapping. AuNSTs demonstrated high optical response under visible spectrum, with maximum absorption at 685 nm, using UV-Vis spectroscopy. Therefore AuNSTs could be involoved into photocatalytic reaction under visible spectrum. AuNSTs demonstrated superior performance in degradation of rhodamine B dye (RB), and disinfection of some pathogenic bacteria. AuNSTs offered enhanced removal efficiency against rhodamine B dye (82.0 ± 0.35% in 135 min) under visible irradiation. Remarkably, under proper conditions of pH = 9, approximately 94 ± 0.55% of a 10 ppm RB solution was effectively photodegraded after 135 min; this could be ascribed to the strong electrostatic attraction between negatively charged AuNSTs surface and positive RB contaminant. This superior photocatalytic activity of AuNSTs could be correlated to high interfacial charge transfer efficiency for Au, and enhanced charge pair separation under visible spectrum. Additionally, AuNSTs exhibited potential antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). AuNSTs demonstrated substantial antibacterial activity via disk diffusion and microbroth dilution tests with zones of inhibition and minimum inhibitory concentrations (MIC) for E. coli (20.0 ± 0.54 mm, 1.25 µg/ml) and S. aureus (23.0 ± 0.35 mm, 0.625 µg/ml), respectively. In conclusion, AuNSTs demonstrated efficient dye removal capabilities along with significant antimicrobial activity against gram-positive and gram-negative bacterial strains.
本研究报道了通过种子介导生长方案简便地制备星形金纳米颗粒。使用透射电子显微镜（TEM）观察发现，金纳米星（AuNSTs）的平均粒径为48nm。通过能量色散X射线光谱（EDX）映射验证了AuNSTs的化学成分。利用紫外可见光谱（UV-Vis）可知，AuNSTs在可见光谱下表现出高光学响应，在685nm处有最大吸收。因此，AuNSTs可参与可见光谱下的光催化反应。AuNSTs在罗丹明B染料（RB）降解和一些病原菌消毒方面表现出优异性能。在可见光照射下，AuNSTs对罗丹明B染料的去除效率有所提高（135分钟内为82.0±0.35%）。值得注意的是，在pH = 9的适当条件下，10 ppm的RB溶液在135分钟后约94±0.55%被有效光降解；这可能归因于带负电荷的AuNSTs表面与带正电荷的RB污染物之间的强静电吸引。AuNSTs这种优异的光催化活性可能与Au的高界面电荷转移效率以及可见光谱下增强的电荷对分离有关。此外，AuNSTs对大肠杆菌（E. coli）和金黄色葡萄球菌（S. aureus）表现出潜在的抗菌活性。通过纸片扩散法和微量肉汤稀释试验，AuNSTs对大肠杆菌（抑菌圈20.0±0.54mm，最低抑菌浓度（MIC）1.25μg/ml）和金黄色葡萄球菌（抑菌圈23.0±0.35mm，MIC 0.625μg/ml）分别表现出显著的抗菌活性。总之，AuNSTs表现出高效的染料去除能力以及对革兰氏阳性和革兰氏阴性细菌菌株的显著抗菌活性。
