Thermally confined shell coating amplifies the photoacoustic conversion efficiency of nanoprobes  

作　　者：Yujiao Shi Huan Qin Sihua Yang Da Xing 

机构地区：[1]Ministry of Education Key Laboratory of Laser Life Science and Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, China

出　　处：《Nano Research》2016年第12期3644-3655,共12页纳米研究（英文版）

基　　金：This research is supported by the National Natural Science Foundation of China （Nos. 91539127, 61331001, 11604105 and 61361160414）, The National High-tech R＆D Program of China （No. 2015AA020901）, The Sdence and Technology Planning Project of Guangdong Province, China （Nos. 2015B020233016, 2014B020215003 and 2014A020215031）.

摘　　要：Efficient probes/contrast agents are highly desirable for good-performance photoacoustic （PA） imaging, where the PA signal amplitude of a probe is dominated by both its optical absorption and the conversion efficiency from absorbed laser energy to acoustic waves. Nanoprobes have a unique micro- mechanism of PA energy conversion due to the size effect, which, however, has not been quantitatively demonstrated and effectively utilized. Here, we present quantitative simulations of the PA signal production process for plasmon- mediated nanoprobes based on the finite element analysis method, which were performed to provide a deep understanding of their PA conversion micromechanism. Moreover, we propose a method to amplify the PA conversion efficiency of nanoprobes through the use of thermally confined shell coating, which allows the active control of the conversion efficiency beyond that of conventional probes. Additionally, we deduced the dependence of the conversion efficiency on the shell properties. Gold-nanoparticles/polydimethylsiloxane nanocomposites were experimentally synthesized in the form of gel and microfilms to verify our idea and the simulation results agreed with the experiments. Our work paves the way for the rational design and optimization of nanoprobes with improved conversion efficiency.Efficient probes/contrast agents are highly desirable for good-performance photoacoustic （PA） imaging, where the PA signal amplitude of a probe is dominated by both its optical absorption and the conversion efficiency from absorbed laser energy to acoustic waves. Nanoprobes have a unique micro- mechanism of PA energy conversion due to the size effect, which, however, has not been quantitatively demonstrated and effectively utilized. Here, we present quantitative simulations of the PA signal production process for plasmon- mediated nanoprobes based on the finite element analysis method, which were performed to provide a deep understanding of their PA conversion micromechanism. Moreover, we propose a method to amplify the PA conversion efficiency of nanoprobes through the use of thermally confined shell coating, which allows the active control of the conversion efficiency beyond that of conventional probes. Additionally, we deduced the dependence of the conversion efficiency on the shell properties. Gold-nanoparticles/polydimethylsiloxane nanocomposites were experimentally synthesized in the form of gel and microfilms to verify our idea and the simulation results agreed with the experiments. Our work paves the way for the rational design and optimization of nanoprobes with improved conversion efficiency.

关 键 词：photoacousticnanoprobes micromechanism conversion efficiency shell coating 

分 类 号：TQ456.04[化学工程—农药化工] TM914.4[电气工程—电力电子与电力传动]