Tuning peptide affinity for biofunctionalized surfaces.

The control of the interaction between biological systems and surfaces plays a major role in the development of bioactive implants. Random absorbance of different compounds of the body liquids attach at the implant site after surgery. This protein layer triggers the activation of immune cells and is a breeding ground for pathogens, which may induce inflammation processes. Many efforts have been made to block these fouling processes such as PEGylation and unspecific coatings. These systems lead to bioinert implant surfaces that lower the inflammation potential of implanted materials. In contrast, the biomimetic approach attempts the functionalization of implant surfaces with compounds such as peptides, proteins, or sugars that form an artificial layer on the implant that corresponds to the naturally occurring extracellular matrix. This enables the controlled recruitment of cells that improve the healing processes or enhance the osseointegration into the implanted material. An improved connection of implants with cells that enhances the healing processes or tightens the connection of implants with the surrounding tissue is obtained by this approach. However, for bioactive functionalization of implant materials, efficient and robust immobilization techniques are required. Peptides owing to their low-toxicity and their multifunctionality are interesting agents that can act as molecular glue to surfaces. Here, an overview is provided of the development of surface binding peptides, the molecular mechanisms of peptide-surface interactions, and the application of surface binding peptides in the development of multifunctional biomaterials that facilitate beneficial characteristics in vitro and in vivo.