Polysaccharide-Coated Thermosets for Orthopedic Applications: From Material Characterization to In Vivo Tests

• Published in: Biomacromolecules Vol. 13; no. 5; pp. 1564 - 1572
• Main Authors: Travan, Andrea, Marsich, Eleonora, Donati, Ivan, Foulc, Marie-Pierre, Moritz, Niko, Aro, Hannu T., Paoletti, Sergio
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 14-05-2012
• Subjects: Adsorption; Applied sciences; Biological and medical sciences; Cell Adhesion - drug effects; Cell Aggregation - drug effects; Cell Proliferation - drug effects; Chemistry, Physical; Coated Materials, Biocompatible - chemistry; Coated Materials, Biocompatible - pharmacology; Coating, metallization, dyeing; Exact sciences and technology; Humans; Hydrogen-Ion Concentration; Machinery and processing; Materials Testing; Medical sciences; Methacrylates - chemistry; Methacrylates - pharmacology; Osmolar Concentration; Osteoblasts - drug effects; Osteoblasts - pathology; Particle Size; Plastics; Polymer industry, paints, wood; Polysaccharides - chemistry; Structure-Activity Relationship; Surface Properties; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Technology of polymers; Technology. Biomaterials. Equipments; Tumor Cells, Cultured; Cell proliferation; Femur; Crosslinked copolymer; Wettability; Fatigue strength; Cell adhesion; Surface properties; Osteoblast; pH; Biocompatibility; Biomaterial; Dip coating; Minipig; Ungulata; Liquid solid adsorption; Nanoindentation; Mechanical properties; Bioactive material; Experimental study; In vitro; Biological activity; Coated material; In vivo; Implanted material; Vertebrata; Mammalia; Adsorbed layers; Chitosan derivatives; Ionic strength; Animal; Oside polymer; Electrostatic deposition; Artiodactyla; Methacrylate copolymer
• ISSN: 1525-7797; 1526-4602
• DOI: 10.1021/bm3002683

The long-term stability and success of orthopedic implants depend on the osseointegration process, which is strongly influenced by the biomaterial surface. A promising approach to enhance implant integration involves the modification of the surface of the implant by means of polymers that mimic the natural components of the extracellular matrix, for example, polysaccharides. In this study, methacrylate thermosets (bisphenol A glycidylmethacrylate/triethyleneglycol dimethacrylate), a widely used composition for orthopedic and dental applications, have been coated by electrostatic deposition of a bioactive chitosan-derivative. This polysaccharide was shown to induce osteoblasts aggregation in vitro, to stimulate cell proliferation and to enhance alkaline phosphatase activity. The coating deposition was studied by analyzing the effect of pH and ionic strength on the grafting of the polysaccharide. Contact angle studies show that the functionalized material displays a higher hydrophilic character owing to the increase of surface polar groups. The mechanical properties of the coating were evaluated by nanoindentation studies which point to higher values of indentation hardness and modulus (E) of the polysaccharide surface layer, while the influence of cyclic stress on the construct was assessed by fatigue tests. Finally, in vivo tests in minipigs showed that the polysaccharide-based implant showed a good biocompatibility and an ability for osseointegration at least similar to that of the titanium Ti6Al4V alloy with roughened surface.