Center for Bio/Molecular Science and Engineering, U.S. Naval Research Laboratory Code 6900, Washington, DC, 20375, USA.
Optical Sciences Division, Code 5600, U.S. Naval Research Laboratory, Washington, DC, 20375, USA.
Small. 2024 Apr;20(14):e2303136. doi: 10.1002/smll.202303136. Epub 2023 Sep 25.
This work investigates the effect of plasmonic gold nanoparticle (AuNP) size on the rate of thermal release of single-stranded oligonucleotides under femtosecond (fs)-pulsed laser irradiation sources. Contrary to the theoretical predictions that larger AuNPs (50-60 nm diameter) would produce the most solution heating and fastest DNA release, it is found that smaller AuNP diameters (25 nm) lead to faster dsDNA denaturation rates. Controlling for the pulse energy fluence, AuNP concentration, DNA loading density, and the distance from the AuNP surface finds the same result. These results imply that the solution temperature increases around the AuNP during fs laser pulse optical heating may not be the only significant influence on dsDNA denaturation, suggesting that direct energy transfer from the AuNP to the DNA (phonon-phonon coupling), which is increased as AuNPs decrease in size, may play a significant role.
这项工作研究了等离子体金纳米粒子（AuNP）尺寸对飞秒（fs）脉冲激光辐照源下单链寡核苷酸热释放速率的影响。与理论预测相反，较大的 AuNP（50-60nm 直径）会产生最多的溶液加热和最快的 DNA 释放，研究发现较小的 AuNP 直径（25nm）导致更快的 dsDNA 变性速率。控制脉冲能量密度、AuNP 浓度、DNA 装载密度和 AuNP 表面的距离，得到相同的结果。这些结果表明，飞秒激光脉冲光热过程中 AuNP 周围溶液温度的升高可能不是 dsDNA 变性的唯一重要影响因素，这表明 AuNP 尺寸减小导致的 AuNP 到 DNA 的直接能量转移（声子-声子耦合）可能起着重要作用。
