Label-Free Imaging

Using advanced scattering-based interference microscopy and novel image data analysis, we develop molecularly specific label-free microscope techniques for characterizing chromatin organization and dynamics in live cells.

Chromatin is a complex of DNA and nuclear proteins that densely packed in the cell nucleus. Chromatin structures and dynamics underlie various nuclear activities, and thus dysfunction of chromatin regulation often leads to diseases. Although the significance of chromatin in nuclear functions has been well recognized, characterization of chromatin organization remains challenging, especially in the live cell nuclei.

We investigate chromatin dynamics in live cells by advanced label-free optical microscope techniques. Using highly sensitive interference microscopy, the scattering light of unlabeled chromatin can be directly measured at a high speed (>1000 fps). By analyzing the dynamic scattering images, we extract the chromatin-specific temporal signal and reconstruct a high-resolution map of chromatin across the whole nucleus. This method is non-invasive and quantitative, enabling long-term accurate measurements of chromatin structures and dynamics in live cells. Collaborating with nuclear biologists, we explore the dynamics in cell nuclei with our novel label-free microscope.

More info about label-free chromatin imaging: "Label-Free Dynamic Imaging of Chromatin in Live Cell Nuclei by High-Speed Scattering-Based Interference Microscopy" ACS Nano (2022).