M. Hoyos-Nogués et al. All-in-one trifunctional strategy: A cell adhesive, bacteriostatic and bactericidal coating for titanium implants. Colloids and Surfaces B: Biointerfaces

M. Hoyos-Nogués, J. Buxadera-Palomero, M.P. Ginebra, J.M. Manero, F.X. Gil, C. Mas-Moruno. All-in-one trifunctional strategy: A cell adhesive, bacteriostatic and bactericidal coating for titanium implants. Colloids and Surfaces B: Biointerfaces 169 (2018) 30–40

doi: 10.1016/j.colsurfb.2018.04.050

Abstract

tStrategies to inhibit initial bacterial adhesion are extremely important to prevent infection on biomate-rial surfaces. However, the simultaneous attraction of desired eukaryotic cells remains a challenge forsuccessful biomaterial-host tissue integration. Here we describe a method for the development of a tri-functional coating that repels contaminating bacteria, kills those that adhere, and promotes osteoblastadhesion. To this end, titanium surfaces were functionalized by electrodeposition of an antifoulingpolyethylene glycol (PEG) layer and subsequent binding of a peptidic platform with cell-adhesive andbactericidal properties. The physicochemical characterization of the samples via SEM, contact angle,FTIR and XPS analysis verified the successful binding of the PEG layer and the biomolecules, withoutaltering the morphology and topography of the samples. PEG coatings inhibited protein adsorption andosteoblast-like (SaOS-2) attachment; however, the presence of cell adhesive domains rescued osteoblastadhesion, yielding higher values of cell attachment and spreading compared to controls (p < 0.05). Finally,the antibacterial potential of the coating was measured by live/dead assays and SEM using S. sanguinisas a model of early colonizer in oral biofilms. The presence of PEG layers significantly reduced bacterialattachment on the surfaces (p < 0.05). This antibacterial potential was further increased by the bacterici-dal peptide, yielding values of bacterial adhesion below 0.2% (p < 0.05). The balance between the risk ofinfection and the optimal osteointegration of a biomaterial is often described as “the race for the surface”,in which contaminating bacteria and host tissue cells compete to colonize the implant. In the presentwork, we have developed a multifunctional coating for a titanium surface that promotes the attachmentand spreading of osteoblasts, while very efficiently inhibits bacterial colonization, thus holding promisefor application in bone replacing applications.