title: Osteoconductive phosphoserine-modified poly({varepsilon}-lysine) dendrons: synthesis, titanium oxide surface functionalization and response of osteoblast-like cell lines.
abstract: The lack of direct bonding between the surface of an implant and the mineralized bony tissue is among the main causes of aseptic loosening in titanium-based implants. Surface etching and ceramic coatings have led to improved osteointegration, but their clinical performance is still limited either by partial bonding or by coating delamination. In this work, a solid-phase synthesis method has been optimized to produce poly(ε-lysine) dendrons, the outermost branching generation of which is functionalized by phosphoserine (PS), a known catalyst of the biomineralization process. The dendrons were deposited onto etched titanium oxide surfaces as a near-to-monolayer film able to induce the formation of a homogeneous calcium phosphate phase in a simulated body fluid over 3 days. The dendron films also stimulated MG63 and SAOS-2 osteoblast-like cells to proliferate at a rate significantly higher than etched titanium, with SAOS-2 also showing a higher degree of differentiation over 14 days. PS-tethered dendron films were not affected by various sterilization methods and UV treatment appeared to improve the cell substrate potential of these films, thus suggesting their potential as a surface functionalization method for bone implants.
authors.affiliation: Brighton Studies in Tissue-mimicry and Aided Regeneration, School of Pharmacy and Biomolecular Sciences, University of Brighton, , Huxley Building, Lewes Road, Brighton, UK.
authors.forename: S T
authors.initials: ST
authors.lastname: Meikle
authors.forename: G
authors.initials: G
authors.lastname: Bianchi
authors.forename: G
authors.initials: G
authors.lastname: Olivier
authors.forename: M
authors.initials: M
authors.lastname: Santin
mesh_terms: D000704:Analysis of Variance; D049109:Cell Proliferation; D050091:Dendrimers / Q000138:chemical synthesis* / Q000737:chemistry*; D010006:Osteoblasts / Q000378:metabolism / Q000502:physiology*; D010768:Phosphoserine / Q000737:chemistry*; D011107:Polylysine / Q000737:chemistry*; D019736:Prostheses and Implants; D060327:Solid-Phase Synthesis Techniques / Q000379:methods; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D050091:Dendrimers; C009495:titanium dioxide; D010768:Phosphoserine; D011107:Polylysine; D014025:Titanium