Fig. 2.

Schematic diagram showing various nano-delivery systems. a Polymicelles consist of a hydrophilic shell, which improves the biocompatibility and stability of the carrier in circulation, and a hydrophobic core for conjugation with hydrophobic anti-cancer drug molecules. b Liposomes have bimolecular lipid layers. The outer hydrophilic layer allows easy passage through cell membranes. The inner layer is hydrophobic and contains drug molecules. c Dendrimers are repetitively branched molecules typically symmetric around the core. Their “tree branch” like structure allows efficient drug carrying capacity and the ease of attaching functional groups for targeted delivery