Intracellular trafficking of particles inside endosomal vesicles is regulated by particle size.

Little comparative information is available on the detailed intracellular dynamics (diffusion, active movement, and distribution mechanisms) of nanoparticles (≤100nm) and sub-micron particles (>100nm). Here, we quantitatively examined the intracellular movements of different-sized particles and of the endosomal vesicles containing those particles. We showed that silica nanoparticles of various sizes (30 to 100nm) had greater motility than sub-micron particles in A549 cells.