pH‐responsive core crosslinked polycarbonate micelles via thiol‐acrylate Michael addition reaction

A facile method for the construction of pH‐responsive core crosslinked micelles (CCLMs) based on polycarbonate was developed. Biodegradable amphiphilic block copolymer monomethoxy poly(ethylene glycol)‐b‐Poly(AC) (mPEG‐b‐poly(AC)) with pendant acrylate group was synthesized by means of ring opening polymerization of acryloyl carbonate (AC). Then CCLMs were obtained via thiol‐acrylate Michael addition reaction between the pendant acrylate group in the hydrophobic block and the crosslinker 1,6‐hexanedithiol. DLS results showed that the CCLMs prepared from mPEG‐b‐poly(AC)₂₅ were more stable than uncrosslinked micelles (UCLMs) upon dilution by 10‐fold DMF. Model drug Coumarin 102 was then encapsulated into the micelles. The pH‐responsive release of coumarin 102 from the CCLMs was demonstrated by fluorescence spectroscopy. The core crosslinked polycarbonate micelles have a potential as efficient intracellular smart drug delivery platforms. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44421.