Preparation and structure-activity investigation of hyperbranched poly(2-methyl-2-oxazoline)-based anti-biofouling surfaces

Elaborating the structure–activity relationship between hyperbranched polymer architecture and the resulting surface antifouling performance is critical for biomedical applications. In this work, a series of poly(2-methyl-2-oxazoline) (PMeOx)-based hyperbranched poly((poly(2-methyl-2-oxazoline) acrylate)-co-(S-(4-vinyl) benzyl S′-propyltrithiocarbonate))s (poly(PMeOxA-co-VBPT)s) with varying degrees of branching (DBs) were synthesized via reversible addition-fragmentation chain transfer polymerization and self-condensing vinyl polymerization (RAFT-SCVP) of poly(2-methyl-2-oxazoline) acrylate (PMeOxA) and S-(4-vinyl) benzyl S′-propyltrithiocarbonate (VBPT). The copolymers were anchored onto surfaces using a material-independent dopamine-assisted co-deposition method. We systematically investigated the hyperbranched structure effects of the copolymers concerning the surface compositions, hydration, morphology, and antifouling properties. Our results demonstrated that the hyperbranched structure provided surfaces with higher PMeOx chain density and superior antifouling properties compared to the linear counterpart. Furthermore, it was found that the antifouling efficacy of the hyperbranched PMeOx-based coatings depended on the surface PMeOx chain densities, which were determined by the DB and PMeOx content in copolymers. Specifically, the PMeOxA(3)-co-VBPT(1)/polydopamine (PDA) coating with optimized formulation displayed the highest resistance to protein, platelet, and cell adsorption (98.4–99.3 % reduction) compared to unmodified surface. Taken together, this work highlights the significant impact of hyperbranched architecture on surface anti-biofouling performances and provides valuable guidelines for manipulating surface properties in applications such as drug delivery, diagnostic, and biosensors.