Directed Assembly of PEGylated-Peptide Coatings for Infection-Resistant Titanium Metal

作者：Xiaojuan Khoo, Paul T. Hamilton, George A. O’Toole, Brian D. Snyder, Daniel J. Kenan, Mark W. Grinstaff · 发表于：Journal of the American Chemical Society · 年份：2009 · DOI：10.1021/ja9020827 · 被引用次数：124 · 研究领域：Corrosion Behavior and Inhibition、Metal and Thin Film Mechanics、Polymer Surface Interaction Studies

Appropriate surface chemistry between a material and its surrounding biological environment is crucial to the eventual integration and performance of any implant, whether metal, plastic, or ceramic. A robust peptide-based coating technology capable of easily modifying the surface of titanium (Ti) metal through noncovalent binding is described. A short peptide possessing affinity for Ti was identified using a phage display screening process and subjected to an amino acid substitution exercise using solid-phase chemical synthesis. Through these studies, the HKH tripeptide motif was elucidated as an important contributor to Ti binding within the Ti-binding peptide. This peptide spontaneously and selectively adsorbs onto a Ti surface from dilute aqueous solution with submicromolar binding affinities as determined by ELISA and quartz crystal microbalance with dissipation monitoring (QCM-D), through a process largely dominated by electrostatic interactions. Atomic force microscopy (AFM) reveals a densely packed peptide adlayer with an average height of approximately 0.5 nm. Subsequently, a PEGylated analogue of the peptide was shown to rapidly coat Ti to afford a nonfouling surface that efficiently blocked the adsorption of fibronectin and significantly reduced the extent of Staphylococcus aureus attachment and biofilm formation in vitro. These PEGylated-peptide coatings show promise in terms of resolving two major hurdles common to implanted metals: (i) nonspecific protein adsorpt...