XPS STUDY OF ELASTIN-SOLUBILIZED PEPTIDES BINDING ONTO APATITE IN ORTHOPEDIC BIOMATERIALS

The adsorption behaviour of elastin-solubilized peptides (ESP) on hydr oxyapatite (HA) was studied by X-ray photoelectron spectroscopy (XPS). The analysis of the data indicated a modification of both the apatiti c surface and the peptide moieties. The aliphatic and aromatic carbon peak increased with respect to the hydrophilic carbon peak indicating a preferential orientation of the peptide molecules interacting essent ially with the apatite surface by their hydrophilic groups. A deproton ation of the amine groups of adsorbed peptides was also observed, reve aling a possibly chemical interaction with the mineral surface. Simult aneously a decrease of the Ca/P ratio of the mineral surface occurred. The orientation of ESP adsorbed on the mineral surface was related to the modification of their reactivity with collagens I + III in the pr ocess of formation of composite biomaterials for orthopaedic applicati ons.