Fig. 7
Schematic illustration of stimuli-responsive and targeted nanoplatforms for the specific delivery of therapeutic agents. A Preparation of the smart nanoplatform via electrostatic and hydrophobic interaction, and the pH-responsive surface charge switch, and GSH-responsive chemical degradation of polymer backbone. B Schematic illustration of and FA-mediated target and pH/GSH-responsive delivery processes: (a) the nanoplatforms show high stability in blood circulation; (b) therefore, they can effectively accumulate in tumor lesions via the EPR effect and receptor-mediated targeting; (c) acidic conditions can cause charge conversion of the nanoplatform; (d) endosome escape of the smart nanoplatform via proton-sponge effect; (e) intracellular GSH stimulation will trigger the release of therapeutic agents for tumor treatment