Figure . (a) Self-assembled Au nanoparticles can take up drug molecules from the solvent phase which can later be released upon disassembly by the change in solvent from water to CD2Cl2. Rightmost: interstitial pores of the assembles that carry the hydrophobic drug molecules. Reprinted with permission © 2017 Nature Publishing Group. (b) pH sensitive Au nanoparticle vesicles as drug carriers. The drug is released by the disassembly of the vesicles by changing the pH from 7.4 to 5.0. Reprinted with permission © 2012, American Chemical Society.