Label-free observation of cytoplasmic organelle structures using interferometric scattering microscopy
ICAMD 2017
Interferometric scattering (iSCAT) microscopy is a new optical imaging technique, recently developed to identify the nano-sized particles without a fluorescent label. While the previous iSCAT studies have been mostly focused on the fast tracking of these particles moving in artificial bio-mimicking systems, we here report on label-free iSCAT imaging of living cells. According to our observations, iSCAT imaging revealed the underlying structures of a variety of cytoplasmic organelles as well as the underside structure of the cells. The contact areas of the cells attached onto a glass substrate, e.g., focal adhesions and filopodia, appear to be dark. We also found a variety of fringe-like features in the cytoplasmic area. An interesting labyrinth-like fringe in a sub-micron scale appears around the outer nucleus membrane, which reflects the folded structures of endoplasmic reticulum and Golgi apparatus. We thus anticipate that the label-free iSCAT microscopy can be used as a powerful tool to shed interferometric light on in vivo structures and dynamics of various intracellular phenomena.