In this video protocol we track - at high speed and in three dimensions - fluorescently labeled lysosomes within living cells, using the orbital tracking method in a modified two-photon microscope.
Anzalone, A., Annibale, P., Gratton, E. 3D Orbital Tracking in a Modified Two-photon Microscope: An Application to the Tracking of Intracellular Vesicles. J. Vis. Exp. (92), e51794, doi:10.3791/51794 (2014).