Thymine modified amphiphilic biodegradable copolymers for photo-cross-linked micelles as stable drug carriers

A photo-cross-linked micelle is synthesized via photodimerization of thymine moieties fabricated from amphiphilic block copolymers (mPEG-b-P(LA-co-MPT). The crosslinking behavior is monitored by UV-Vis spectra and ¹H NMR. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) showed that cross-linked micelles had smaller sizes than their uncross-linked precursors. In vitro studies reveal that cross-linking of the micelle cores results in a slow drug release and faster cellular uptake in comparison with uncross-linked ones in MCF-7 and Hela cells. Moreover, the paclitaxel (PTX)-loaded core-cross-linked micelles exhibit similar anticancer efficacy as free PTX. This work provides a convenient tool for designing a more stable structure in the blood circulation to realize a controlled drug delivery. Photo-cross-linked micelles are prepared via photodimerization of the thymine moieties fabricated from amphiphilic block copolymers (mPEG-b-P(LA-co-MPT). The cross-linked micelles have more stable structure and can be a promising tool for intelligent drug delivery.