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.

中文翻译：

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红外光热显微镜检测含腈的小分子

红外（IR）光热显微镜（IR-PTM）的使用正在兴起，以对各种样品中的化学物质进行成像。在这项研究中，我们证明了使用腈基作为振动标签来成像低水本底区域中的目标分子。我们对细胞中的三氟甲氧基羰基氰化物苯hydr（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证实了高空间分辨率。我们对FCCP处理的HeLa细胞进行了成像，并确认光热信号确实是由脂质液滴中的振动标签产生的。我们还通过刺激拉曼散射（SRS）显微镜将结果与腈成像进行了比较。从计算结果和实验结果来看，