title: Silica-polyethylene glycol hybrids synthesized by sol-gel: Biocompatibility improvement of titanium implants by coating.
abstract: Although metallic implants are the most used in dental and orthopaedic fields, they can early fail due to low tissue tolerance or osseointegration ability. To overcome this drawback, functional coatings can be applied on the metallic surface to provide a firm fixation of the implants. The objective of the present study was twofold: to synthesize and to characterize silica/polyethylene glycol (PEG) hybrid materials using sol-gel technique and to investigate their capability to dip-coat titanium grade 4 (Ti-gr4) substrates to improve their biological properties. Various hybrid systems have been synthesized by changing the ratio between the organic and inorganic phases in order to study the influence of the polymer amount on the structure and, thus, on the properties of the coatings. Fourier transform infrared (FTIR) spectroscopy and solid state Nuclear Magnetic Resonance (NMR) allowed us to detect the formation of hydrogen bonds between the inorganic sol-gel matrix and the organic component. SEM analysis showed that high PEG content enables to obtain crack free-coating. Moreover, the effective improvement in biological properties of Ti-gr4 implants has been evaluated by performing in vitro tests. The bioactivity of the hybrid coatings has been showed by the hydroxyapatite formation on the surface of SiO2/PEG coated Ti-gr4 substrates after soaking in a simulated body fluid and the lack of cytotoxicity by the WST-8 Assay. The results showed that the coated substrates are more bioactive and biocompatible than the uncoated ones and that the bioactivity is not significantly affected by PEG amount whereas its addition makes the films more biocompatible.
authors.affiliation: Department of Industrial and Information Engineering, Second University of Naples, Via Roma 21, 81031 Aversa, Italy. Electronic address: michelina.catauro@unina2.it.
authors.forename: M
authors.initials: M
authors.lastname: Catauro
authors.affiliation: Department of Industrial and Information Engineering, Second University of Naples, Via Roma 21, 81031 Aversa, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Bollino
authors.affiliation: Department of Industrial and Information Engineering, Second University of Naples, Via Roma 21, 81031 Aversa, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Papale
authors.affiliation: Department of Chemistry, University of Pavia and INSTM, Via Taramelli 12, 27100 Pavia, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Ferrara
authors.affiliation: Department of Chemistry, University of Pavia and INSTM, Via Taramelli 12, 27100 Pavia, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Mustarelli
mesh_terms: D000818:Animals; D002460:Cell Line; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry; D008422:Materials Testing / Q000379:methods; D051379:Mice; D008855:Microscopy, Electron, Scanning / Q000379:methods; D041681:NIH 3T3 Cells; D044367:Phase Transition; D011092:Polyethylene Glycols / Q000737:chemistry*; D019736:Prostheses and Implants; D012822:Silicon Dioxide / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D014025:Titanium / Q000737:chemistry*
chemical_list: D020099:Coated Materials, Biocompatible; D011092:Polyethylene Glycols; D012822:Silicon Dioxide; D017886:Durapatite; D014025:Titanium
keywords: Bioactivity; Biocompatibility; Silica–polyethylene glycol hybrids; Sol–gel process