Abstract
Intracellular transport plays an important role in maintaining the physiological functions of cells. Here, we describe a protocol for 3D single-particle tracking within living cells. We detail the use of a two-focal imaging system and the analytical steps for quantifying 3D transport dynamics. This protocol can be used to characterize the intracellular diffusion and trafficking of macromolecules, nanoparticles, and endocytic vesicles in adherent cells. For complete details on the use and execution of this protocol, please refer to Jiang et al. (2022).