A smart flower-like polymeric micelle for pH-triggered anticancer drug release

Novel pH-responsive flower-like micelles were developed to provide the mechanism for pH-triggered drug release from drug carriers. The micelles (particle size: ∼165 nm; critical micelle concentration (CMC): ∼4 μg/ml), constructed from poly(Nɛ-(3-diethylamino)propyl isothiocyanato-l-lysine)-b-poly(ethylene glycol)-b-poly(l-lactide) [poly(DEAP-Lys)-b-PEG-b-PLLA], were designed to have a self-assembled flower-like arrangement consisting of two hydrophobic blocks [deprotonated poly(DEAP-Lys) block and PLLA block] and a petal-like hydrophilic PEG block at physiological pH. As the pH decreases to slightly acidic pH (