Photo-cross-linked poly(ether amine) micelles for controlled drug release

In order to improve the stability of micelles and decrease the burst release of loaded drugs, photo-crosslinked micelles were prepared via photodimerization of the coumarin moiety on amphiphilic poly(ether amine) (PEAC). The structures of the obtained monomer and polymers were confirmed by Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-vis), H-1 NMR and C-13 NMR (Nuclear Magnetic Resonance, NMR). PEAC could self-assemble into micelles by directly dispersing in water with a hydrophobic coumarin core and a hydrophilic poly(ethylene glycol) (PEG) shell. The photo-cross-linking process of the PEAC micelles was monitored by UV-vis spectroscopy. The morphology and size distribution of the micelles was characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS). Anticancer drug doxorubicin (DOX) was loaded into the micelles during the process of micelle formation. Photo-cross-linked micelles showed slower drug release and cellular uptake in comparison with the uncross-linked micelles. And both DOX-loaded micelles displayed pH-sensitive release behaviours. Moreover, the DOX-loaded photo-cross-linked micelles exhibit comparative anticancer efficacy as free DOX. These results indicated that photo-cross-linked PEAC micelles can be used as potential drug carriers for intelligent drug delivery.