Nonfouling surface coatings based on poly(2-methyl-2-oxazoline)

Surface fouling, i.e. the non-specific surface adhesion of proteins, bacteria and higher organisms, poses a severe problem in many areas ranging from modern diagnostic and therapeutic medical devices to food processing and food wrapping technology to corrosion prevention and marine technology. One approach to address these problems is to coat surfaces with nonfouling polymers. The properties of a new class of nonfouling polymer coatings made from poly(2-methyl-2-oxazoline) (PMOXA) were investigated here in comparison with the most frequently used polymer in this context, poly(ethylene glycol) (PEG). Both polymers were side-chain grafted onto a polycationic poly-L-lysine (PLL) backbone. The PMOXA graft copolymers spontaneously self-assembled to form monolayers; on negatively charged surfaces. PMOXA surface coatings were as efficient as PEG-based coatings in suppressing protein and bacterial adsorption. The minimal number of side chain monomer units per surface area that are needed to obtain fully resistant surfaces was lower though for PMOXA than for PEG graft copolymers as a result of the higher molecular weight of the PMOXA monomer unit.