Fig. 8

Various ways in which nanocarriers can transport drugs to tumors, using polymeric nanoparticles as a representative example. To achieve passive tissue targeting, the nanoparticles extravasate through the tumor vasculature due to increased permeability and inefficient lymphatic drainage (ePr effect). Active cellular targeting can be accomplished by modifying the surface of the nanoparticles with ligands that promote recognition and binding to specific cells. Nanoparticles can then either (i) release their contents in close proximity to the target cells; (ii) adhere to the cell membrane and serve as an extracellular sustained-release drug reservoir; or (iii) become internalized by the cell. Reprint from [132] with a permission from Springer Nature