Thermoresponsive zwitterionic poly(phosphobetaine) microgels: Effect of<scp>macro‐RAFT</scp>chain length and cross‐linker molecular weight on their antifouling properties

Adsorption of proteins on biological surfaces is a detrimental phenomenon that reduces the work-life implants in various biomedical applications. Here, we synthesized new class thermoresponsive zwitterionic poly(phosphobetaine) (PMPC) microgel with excellent surface antifouling property by macro-RAFT mediated thiol-epoxy click reaction. End-group modified PMPC homopolymers well-defined molecular weight and narrow dispersity were grafted onto poly(N-vinylcaprolactam-co-glycidyl methacrylate) (PVG) copolymer backbone followed addition cross-linker, leading to formation. While no upper critical solution temperature (UCST) was found methacrylate-g-2-methacryloyloxyethyl phosphorylcholine) (PVGP) graft copolymers, corresponding microgels exhibited both UCST lower (LCST) transitions, related swelling collapse poly (N-vinylcaprolactam) (PVCL) components respectively. An increase chain length increased shifting LCST higher temperatures, due ability groups coordinate large number water molecules. The effect variation weights amphiphilic poly(ethylene glycol) diamine (PEG-NH2) cross-linker also reflected salt responsiveness microgels. efficacy as potential materials further studied fluorescence microscopy XPS analysis coatings treated FITC-BSA pure BSA Lower protein adsorption observed for PMPC, whereas, using PEG-NH2 displayed greater their surfaces.