Slippery organogel coatings on nitric oxide-releasing polymers for dual-action antibiofouling properties

Slippery organogels are anti-adhesive and antibiofouling surfaces wherein infused oil acts as a passive adhesion-resistant barrier. However, a) depletion of the infused lubricant owing to migration/volatilization, b) inability to limit platelet activation, and c) ineffectiveness to eliminate microbes demands co-integration with bioactivity to ensure unhindered antifouling behavior. Thus, the antibiofouling effectiveness of biomaterial surfaces can be enhanced via the combination of a passive slippery coating with a bioactive agent. This report investigates the integrative effect of a self-healing, passive slippery organogel coating applied on a bioactive polymer to combat biofouling both in vitro and in vivo. Herein, incorporation of the endogenously produced antithrombotic and antibacterial gasotransmitter, nitric oxide, in medical-grade polymers constitutes the bioactive avenue followed by coating with bis(3-aminopropyl) terminated polydimethylsiloxane, isophorone diisocyanate cross-linker, and silicone oil to embed the passive organogel coating. The reported cytocompatible and hemocompatible biomaterial significantly reduces protein adsorption and platelet adhesion (>65%), inhibits bacterial biomass accumulation in a 48 h drip flow model (>73%), and eliminates planktonic bacterial growth. Importantly, the slippery organogel-coated bioactive polymer demonstrates a significant reduction in thrombus formation in a 4 h extracorporeal circuit rabbit model (∼87%). The in vitro and in vivo results demonstrate applicability of the slippery organogel-coated bioactive polymers in combating biofouling of medical devices.