DDM is a microscopy technique that allows performing light scattering experiments using a simple optical microscope. This project uses collective cell migration to investigate if DDM could be used to detect changes in cell phenotype and/or functions by comparing migration schemes.
The microscope incubator
To produce time-lapse videos that can be used for DDM analysis, it is essential that the focal plane of the microscope do not drift during the image acquisition. Previously, only a small incubator, which fit on the microscope stage, was used to maintain cells at 37 °C. But then even the smallest change in room temperature induced a thermal expansion of the optical components of the microscope, which resulted in focus drift. An incubator in which the microscope could sit was then fabricated to maintain the temperature of the microscope constant but also maintain the cells at an appropriate temperature.
Acquisition and analysis
A computer-controlled shutter is integrated to the microscope to keep cells in the dark between snapshots. An Ethernet camera is connected to the microscope and interfaced with LabView to perform image acquisition. LabView synchronizes with the shutter to capture images. The DDM analysis of the time-lapse videos is performed using a Python script.