[Review of Scientific Instruments] Lagrangian 3D tracking of fluorescent microscopic objects in moti
We describe the development of a tracking device, mounted on an epi-fluorescent inverted microscope, suited to obtain time resolved 3D Lagrangian tracks of fluorescent passive or active micro-objects in microfluidic devices. The system is based on real-time image processing, determining the displacement of a x, y mechanical stage to keep the chosen object at a fixed position in the observation frame. The z displacement is based on the refocusing of the fluorescent object determining the displacement of a piezo mover keeping the moving object in focus. Track coordinates of the object with respect to the microfluidic device as well as images of the object are obtained at a frequency of several tenths of Hertz. This device is particularly well adapted to obtain trajectories of motile micro-organisms in microfluidic devices with or without flow.
T. Darnigea), N. Figueroa-Moralesa), P. Bohec, A. Lindner, and E. ClémentHide Affiliations Laboratoire Physique et Mécanique des Milieux Hétérogènes, CNRS- ESPCI Paris, PSL Research University, Universités Pierre et Marie Curie and Denis Diderot, Sorbonne-Universités, 10, Rue Vauquelin, Paris, France a)T. Darnige and N. Figueroa-Morales contributed equally to this work.