CSIR-Central Scientific Instruments Organisation, Chandigarh, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
J Appl Microbiol. 2022 Aug;133(2):569-578. doi: 10.1111/jam.15588. Epub 2022 Apr 30.
This paper aims to investigate the photo-thermally enhanced antimicrobial efficacy of triangular silver nanoplates for a broad range of harmful pathogens viz., Gram-negative bacteria (Escherichia coli), Gram-positive bacteria (Staphylococcus aureus), and fungus (Candida albicans).
Triangular silver nanoplates were synthesized using the chemical method and were characterized for optical absorption, size and morphology, surface charge and concentration via UV-Vis spectroscopy, transmission electron microscopy, zeta potential analysis and inductively coupled plasma mass spectrometry, respectively. Furthermore, the photo-thermally enhanced antimicrobial efficacy of the triangular silver nanoplates (10 μg/ml concentration) was evaluated on broadband near-infrared irradiation. The photothermal response shows that for the fixed concentration of silver nanoplates, the smaller-sized nanoplates (52 nm) lead to higher temperature rise than larger-sized nanoplates (68 nm). It is demonstrated that within a short exposure duration of 15 min, the photothermal activation of silver nanoplates led to ~5 log CFU/ml reduction for E. coli and C. albicans, and ~7 log CFU/ml reduction for S. aureus from a considerably high initial load of 5 × 10 CFU/ml.
The present study demonstrates that photo-thermally enhanced triangular silver nanoplates possess much stronger antimicrobial efficacy over a short exposure duration of few minutes and exhibits the applicability for a broad range of pathogens.
The study is highly significant and explains the eradication of broad-spectrum of microbial pathogens by photo-thermally enhanced silver nanoplates in short exposure duration with low nanoparticle concentration, which is useful for diverse antibacterial and antifungal applications.
本研究旨在探究三角银纳米板在广谱有害病原体（如革兰氏阴性菌[大肠杆菌]、革兰氏阳性菌[金黄色葡萄球菌]和真菌[白色念珠菌]）中的光热增强抗菌功效。
采用化学方法合成三角银纳米板，并通过紫外-可见光谱、透射电子显微镜、Zeta 电位分析和电感耦合等离子体质谱分别对其光学吸收、尺寸和形态、表面电荷和浓度进行了表征。此外，还在宽带近红外辐射下评估了三角银纳米板的光热增强抗菌功效（10μg/ml 浓度）。光热响应表明，对于固定浓度的银纳米板，较小尺寸的纳米板（52nm）比较大尺寸的纳米板（68nm）导致更高的温升。结果表明，在 15 分钟的短暴露时间内，银纳米板的光热激活使大肠杆菌和白色念珠菌的 CFU/ml 减少了5 个对数，金黄色葡萄球菌的 CFU/ml 减少了7 个对数，初始负载高达 5×10 个 CFU/ml。
本研究表明，光热增强的三角银纳米板在短暴露时间内（几分钟）具有更强的抗菌功效，适用于广谱病原体。
该研究意义重大，解释了在短暴露时间内，低纳米粒子浓度的光热增强银纳米板可有效消除广谱微生物病原体，这对各种抗菌和抗真菌应用非常有用。
