Surface functionalization of poly (dimethyl siloxane) (PDMS) has been an ongoing challenge that has limited this material’s applications. Plasma treatment followed by silane surface grafting has been the primary method of functionalization and requires expensive plasma chambers, dangerous silane-containing chemicals, and the necessity of functionalization immediately after the plasma treatment process due to surface rearrangement that can occur in <1 day. These challenges have led to the development of adsorption-based modifications of PDMS, which often rely on proteins or ligands adsorbing to the surface, which often are unstable in certain environments, not mechanically robust, and temporary. To address these challenges, we have synthesized a functional surface segregating zwitterionic copolymer that can be used to functionalize PDMS before or after plasma treatment. These additives are incorporated during the mixing of uncured PDMS and can be used to functionalize the surface at any point after curing. These polymers can react with primary amines in aqueous or organic solvents, and through these reactions, we have been able to show an increase in protein adsorption, small molecule functionalization, and increased cell adhesion. These additives were characterized by X-ray photoelectron spectroscopy (XPS), water contact angle changes, and fluorescence microscopy to show their functionality. Through these additives, we have developed a novel method of robustly functionalizing PDMS, opening the potential applications for these materials.
