Noncontact photoacoustic lipid imaging by remote sensing on first overtone of the C-H bond  

作　　者：Guyue Hu Qiao Ran Beth Wing Lam So Mingsheng Li Jiawei Shi Xin Dong Jiqiang Kang Kenneth K.Y.Wong 

机构地区：[1]The University of Hong Kong,Faculty of Engineering,Department of Electrical and Electronic Engineering,Hong Kong,China [2]The University of Hong Kong,School of Biological Sciences,Hong Kong,China [3]The University of Hong Kong,School of Biomedical Sciences,LKS Faculty of Medicine,Pokfulam,Hong Kong,China [4]Hong Kong Science Park,Advanced Biomedical Instrumentation Centre,Hong Kong,China

出　　处：《Advanced Photonics Nexus》2023年第2期133-140,共8页先进光子学通讯（英文）

基　　金：supported by the Research Grants Council of the Hong Kong Special Administrative Region of China(Grant Nos.HKU 17210522,HKU C7074-21G,HKU 17205321,HKU 17200219,HKU 17209018,and CityU T42-103/16-N);the Health@InnoHK Program of the Innovation and Technology Commission of the Hong Kong SAR Government.

摘　　要：Lipid imaging by conventional photoacoustic microscopy subjects to direct contact sensing with relatively low detection bandwidth and sensitivity,which induces superficial imaging depth and low signalto-noise ratio(SNR)in practical imaging scenarios.Herein,we present a photoacoustic remote sensing microscopy for lipid distribution mapping in bio-tissue,featuring noncontact implementation,broad detection bandwidth,deep penetration depth,and high SNR.A tailored high-energy pulsed laser source with a spectrum centered at 1750 nm is used as the excitation beam,while a cofocused 1550 nm continuous-wave beam is used as the probe signal.The pump wavelength is selected to overlap the first overtone of the C-H bond in response to the intensive absorption of lipid molecules,which introduces a much-enhanced SNR(55 dB)onto photoacoustic remote sensing(PARS)signals.Meanwhile,the optical sensing scheme of the photoacoustic signals provides broadband detection compared to the acoustic transducer and refrains the bio-samples from direct contact operations by eliminating the ultrasonic coupling medium.Taking merits of the high detection sensitivity,deep penetration depth,broadband detection,and high resolution of the PARS system,high-quality tissue scale lipid imaging is demonstrated in a model organism and brain slice.

关 键 词：photoacoustic microscopy remote sensing lipid imaging near-infrared imaging label-free NONCONTACT 

分 类 号：TN2[电子电信—物理电子学]