Laboratory of Biomedical Optics and Imaging, Federal University of Pernambuco, Av. da Arquitetura Recife, Pernambuco, 50740-550, Brazil; Department of Nuclear Energy, Federal University of Pernambuco, Av. Prof. Luiz Freire, 1000 Recife, Pernambuco, 50740-545, Brazil.
Laboratory of Biomedical Optics and Imaging, Federal University of Pernambuco, Av. da Arquitetura Recife, Pernambuco, 50740-550, Brazil.
Photodiagnosis Photodyn Ther. 2024 Oct;49:104309. doi: 10.1016/j.pdpdt.2024.104309. Epub 2024 Aug 21.
The use of photothermal processes has been proven effective in the control of microbial infections. Simultaneously, the localized surface plasmon resonance phenomena in metallic nanoparticles have been explored as an alternative strategy to achieve highly efficient localized heating. In this work, we propose the use of selected nanoheaters to improve the efficiency of fungal photothermal inactivation of Candida albicans through size optimization of plasmonic gold nanorods. Here, the optical heating of polyethylene glycol coated gold nanorods of varying sizes is evaluated, both theoretically and experimentally. A size-dependent computational approach was applied to identify metallic nanorods with maximized thermal performance at 800 nm, followed by the experimental comparison of optimal and suboptimal nanoheaters. Comparison among samples show temperatures of up to 53.0 °C for 41×10 nm gold nanorods against 32.3 °C for 90×25 nm, a percentage increase of ∼63% in photothermal inactivation assessments. Our findings reveal that gold nanorods of 41×10 nm exhibit superior efficiency in near-infrared (800 nm) photothermal inactivation of fungi, owing to their higher light-thermal conversion efficiency. The identification of high performance metallic nanoheaters may lead to the reduction of the nanoparticle dose used in plasmonic-based procedures and decrease the laser exposure time needed to induce cell death. Moreover, our results provide insights to better exploit plasmonic nanoparticles on photothermal inactivation protocols.
光热过程已被证明在控制微生物感染方面非常有效。同时，金属纳米粒子中的局域表面等离激元共振现象已被探索作为实现高效局域加热的替代策略。在这项工作中，我们提出使用选定的纳米加热器通过优化等离子体金纳米棒的尺寸来提高白色念珠菌真菌光热失活的效率。在这里，从理论和实验两方面评估了不同尺寸的聚乙二醇包覆金纳米棒的光学加热。应用尺寸相关的计算方法来确定在 800nm 处具有最大热性能的金属纳米棒，然后对最佳和次优纳米加热器进行实验比较。样品之间的比较表明，41×10nm 的金纳米棒的温度高达 53.0°C，而 90×25nm 的金纳米棒的温度为 32.3°C，光热失活评估的百分比增加约为 63%。我们的研究结果表明，由于其更高的光热转换效率，41×10nm 的金纳米棒在近红外（800nm）光热灭活真菌方面表现出更高的效率。高性能金属纳米加热器的鉴定可能会导致减少基于等离子体的程序中使用的纳米颗粒剂量，并减少诱导细胞死亡所需的激光暴露时间。此外，我们的结果为更好地利用光热灭活方案中的等离子体纳米颗粒提供了见解。
