Enhancing Osseointegration and Mitigating Bacterial Biofilms on Medical-Grade Titanium with Chitosan-Conjugated Liquid-Infused Coatings
Abstract Titanium alloys, in particular, medical-grade Ti-6Al-4V is heavily used in orthopaedic applications due to its high moduli, strength, and biocompatibility. Implant infection can result in biofilm formation and failure of prosthetics. The formation of a biofilm on implants protect bacteria from antibiotics and the immune response, resulting in the propagation of the infection and ultimately result in device failure. Recently, slippery liquid-infused surfaces (LIS) have been investigated for their stable liquid interface, which provide excellent repellent properties to suppress biofilm formation. One of the current limitations of LIS coatings lies in the indistinctive repellency of bone cells in orthopaedic applications, therefore causing poor integration between tissue and implant. Here, we report a chitosan impregnated LIS coating that facilitates cell adhesion and osseointegration while preventing biofilm formation. Our results indicate that chitosan-conjugated LIS increased cell adhesion of osteoblast-like SaOS-2 cells and significantly promoted proliferation compared to conventional titanium liquid-infused surfaces. Furthermore, the chitosan conjugated LIS significantly reduced biofilm formation of methicillin-resistant Staphylococcus aureus (MRSA) when compared to untreated and chitosan-coated titanium. Our engineered coating can be easily modified with other biopolymers or capture molecules to be applied to other biomaterials where both tissue integration and biofilm prevention is needed.