Mercapto-Responsive Polymeric Nano-carrier Capable to Release Sulfur Dioxide

Abstract

Stimuli-responsive polymeric nano-capsules toward a specific biological signaling molecule show great potential in the fabrication of smart and efficient controlled drug vehicles. Herein, we design and synthesize an amphiphilic diblock copolymer of PEG45-b-PDNPSEMA16 (PEG = poly(ethylene glycol), PDNPSEMA = poly(2- (((2,4-dinitrophenyl)sulfonyl)oxy)ethyl methacrylate), the subscripts represent the mean number of repeat unit of each block) with 2,4-dinitrophenylsulfonyl ester. PEG45-b-PDNPSEMA16 amphiphilic diblock copolymer could self-assemble to form spherical micelles in aqueous media. The core of formed micelles contains hydrophobic PDNPSEMA domains, which is able to load hydrophobic species within the core. The 2,4-dinitrophenylsulfonyl ester moiety can be selectively cleaved upon incubating with mercapto-containing species, to give SO2, which can serve as a SO2 carrier. Thus, mercapto-containing species exhibit the ability to alter the amphiphilicity and further the self-assembled behavior of PEG45-b-PDNPSEMA16. The release of payloads in the core of micelles can be accelerated specifically by triggering mercapto-containing species. We envisage that this polymer model could broaden the scope of biological molecule responsive macromolecular systems and provide a new platform to fabricate mercapto-responsive biomedicine materials.