Photo-crosslinked poly(ethylene glycol)-b-poly(ε-caprolactone) nanoparticles for controllable paclitaxel release

Novel biodegradable core-crosslinked nanoparticles (CNPs) consisting of methoxy poly(ethylene glycol)-block-poly(E-caprolactone-co--cinnamoyloxy-E-caprolactone) (mPEG-b-P(CL-co-CCL)) were prepared and evaluated for paclitaxel (PTX) delivery. mPEG(113)-b-P(CL65.2-co-CCL10.1) had a higher drug loading efficiency (95%) compared to mPEG(113)-b-PCL93.1 (43%). The stability of NPs has been largely improved and PTX release was significantly inhibited by crosslinking via UV irradiation at =254nm. MTT assays demonstrated that both blank non-crosslinked and crosslinked NPs showed low cytotoxicity to NCL-H460 cells while PTX-loaded non-crosslinked and crosslinked NPs exhibited obvious cytotoxicity against NCL-H460 cells, and the cytotoxicity was both dose-dependent and time-dependent. Furthermore, after 48h incubation the cell viability of PTX-loaded crosslinked NPs was lower compared to that of PTX-loaded non-crosslinked NPs or free PTX. These properties indicated that CNPs prepared from mPEG-b-P(CL-co-CCL) have great potentials as carriers for drug delivery.