Novel Anti‐Biofouling Soft Contact Lens: l ‐Cysteine Conjugated Amphiphilic Conetworks via RAFT and Thiol–Ene Click Chemistry

A unique l ‐cysteine conjugated antifouling amphiphilic conetwork (APCN) is synthesized through end‐crosslinking of well‐defined triblock copolymers poly(allyl methacrylate)‐ b ‐poly(ethylene glycol)‐ b ‐poly(allyl methacrylate) via a combination of reversible addition‐fragmentation chain transfer (RAFT) polymerization and thiol–ene “click” chemistry. The synthesized poly(ethylene glycol) macro‐RAFT agent initiates the polymerization of allyl methacrylate in a controlled manner. The vinyl pendant groups of the precursor partially conjugate with l ‐cysteine and the rest fully crosslink with mercaptopropyl‐containing siloxane via thiol–ene click chemistry under UV irradiation into APCNs, which show distinguished properties, that is, excellent biocompatibility, more than 39.6% water content, 101 barrers oxygen permeability, optimized mechanical properties, and more than 93% visible light transmittance. What's more, the resultant APCNs exhibit eminent resistance to protein adsorption, where the bovine serum albumin and lysozyme adsorption are decreased to 12 and 21 µg cm −2 , respectively. The outstanding properties of APCNs depend on the RAFT controlled method, which precisely designs the hydrophilic/hydrophobic segments and eventually greatly improves the crosslinking efficiency and homogeneity. Meantime, the l ‐cysteine monolayer can effectively reduce the surface hydrophobicity and prevent protein adsorption, which exhibits the viability for antifouling surface over and under ophthalmic devices, suggesting a promising soft contact lens.