Fig. 2

Depiction and characterization of zwitterionic coatings on PEEK substrates. (a) Chemical structures of the molecules involved. (b) Schematic description of the three chemical strategies used to functionalize the PEEK surfaces with the two zwitterions. (c) WCA measurements on bare PEEK samples and the coated ones. *** = p < 0.001, **** = p < 0.0001. PEEK = polyether-ether-ketone, SBMA = [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide, MPC = 2-methacryloyloxyethyl phosphorylcholine, PDA = polydopamine, DMAPAA = N-[3-(dimethylamino)propyl]acrylamide].