Quaroni Luca, Pogoda Katarzyna, Wiltowska-Zuber Joanna, Kwiatek Wojciech M
Department of Experimental Physics of Complex Systems, Institute of Nuclear Physics, Polish Academy of Sciences PL-31342 Kraków Poland
Department of Physical Chemistry and Electrochemistry, Faculty of Chemistry, Jagiellonian University PL-30387 Kraków Poland.
RSC Adv. 2018 Jan 12;8(5):2786-2794. doi: 10.1039/c7ra10240b. eCollection 2018 Jan 9.
Atomic force microscopy - infrared (AFM-IR) spectroscopy allows spectroscopic studies in the mid-infrared (mid-IR) spectral region with a spatial resolution better than is allowed by the diffraction limit. We show that the high spatial resolution can be used to perform spectroscopic and imaging studies at the subcellular level in fixed eukaryotic cells. We collect AFM-IR images of subcellular structures that include lipid droplets, vesicles and cytoskeletal filaments, by relying on the intrinsic contrast from IR light absorption. We also obtain AFM-IR absorption spectra of individual subcellular structures. Most spectra show features that are recognizable in the IR absorption spectra of cells and tissue obtained with FTIR technology, including absorption bands characteristic of phospholipids and polypeptides. The quality of the spectra and of the images opens the way to structure and composition studies at the subcellular level using mid-IR absorption spectroscopy.
原子力显微镜-红外（AFM-IR）光谱技术能够在中红外（mid-IR）光谱区域进行光谱研究，其空间分辨率优于衍射极限所允许的范围。我们证明，这种高空间分辨率可用于对固定的真核细胞进行亚细胞水平的光谱和成像研究。我们通过利用红外光吸收产生的固有对比度，收集了包括脂滴、囊泡和细胞骨架细丝在内的亚细胞结构的AFM-IR图像。我们还获得了单个亚细胞结构的AFM-IR吸收光谱。大多数光谱显示出在用傅里叶变换红外光谱（FTIR）技术获得的细胞和组织的红外吸收光谱中可识别的特征，包括磷脂和多肽的特征吸收带。光谱和图像的质量为利用中红外吸收光谱进行亚细胞水平的结构和组成研究开辟了道路。
