Temperature and Salt Responsive Zwitterionic Polysulfamide-based Nanogels with Surface Regeneration Ability and Controlled Drug Release
While zwitterionic polymers with consistent anti-fouling ability have been extensively studied, the responsive versions withswitchable anti-fouling ability were much less explored. Herein, a novel zwitterionic polysulfamide-based monomer named (2-((2-(methacryloyloxy)ethyl) dimethylammonio)acetyl)(phenylsulfonyl)amide (MEDAPA) was firstly developed and a series of nanogels based on MEDAPA (named as PMEDAPA) with different degree of crosslinking were facilely fabricated by precipitation polymerization. The obtained PMEDAPA nanogels exhibited reversible heating-induced swelling and cooling-induced shrinking, exhibiting the upper critical solution temperature (UCST) type of thermo-responsiveness. Furthermore, PMEDAPA nanogels kept shrinking state in water whereas became highly swollen in salt solutions, displaying the obvious salt-responsiveness induced by anti-polyelectrolyte effect.Owing to the temperature or salt induced hydrophilic-hydrophobic transition, PMEDAPA nanogels displayed bio-adhesion behavior at low temperature or in water and anti-fouling behavior at high temperature or in salt solutions. Notably, PMEDAPA nanogels absorbed protein significantly in water whereas detached protein sufficiently in 0.9 wt% NaCl solutions, which could be reversible for more than 8 times without sacrificing the separation efficiency. In addition, doxorubicin could be effectively loaded into PMEDAPA nanogels which showed controlled drug release at different temperatures. Therefore, PMEDAPA nanogels may be an intriguing system for the fabrication of intelligent interface with facile regenerative properties and smart drug delivery carriers in the future.