Tai Fangfang, Koike Kota, Kawagoe Hiroyuki, Ando Jun, Kumamoto Yasuaki, Smith Nicholas I, Sodeoka Mikiko, Fujita Katsumasa
Department of Applied Physics, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
Analyst. 2021 Apr 7;146(7):2307-2312. doi: 10.1039/d0an02198a. Epub 2021 Feb 23.
The use of infrared (IR) photothermal microscopy (IR-PTM) is emerging for imaging chemical substances in various samples. In this research, we demonstrated the use of a nitrile group as a vibrational tag to image target molecules in the low water-background region. We performed IR photothermal imaging of trifluoromethoxy carbonyl cyanide phenylhydrazone (FCCP) in cells and confirmed the high spatial resolution by photothermal detection using visible light as a probe beam. We imaged FCCP-treated HeLa cells and confirmed that the photothermal signal was indeed produced from the vibrational tag in lipid droplets. We also compared the results with nitrile imaging by stimulated Raman scattering (SRS) microscopy. From both the calculated and experimental results, IR-PTM demonstrated a signal-to-noise ratio (SNR) several tens of times better than that of SRS microscopy on the basis of the same power input.
红外（IR）光热显微镜（IR-PTM）在对各种样品中的化学物质进行成像方面正崭露头角。在本研究中，我们展示了使用腈基作为振动标记物，以在低水背景区域对目标分子进行成像。我们对细胞中的三氟甲氧基羰基氰化物苯腙（FCCP）进行了红外光热成像，并通过使用可见光作为探测光束的光热检测确认了高空间分辨率。我们对经FCCP处理的HeLa细胞进行了成像，并确认光热信号确实由脂滴中的振动标记物产生。我们还将结果与受激拉曼散射（SRS）显微镜的腈成像结果进行了比较。从计算结果和实验结果来看，基于相同的功率输入，IR-PTM的信噪比（SNR）比SRS显微镜高出几十倍。
