title: Terminal sterilization of BisGMA-TEGDMA thermoset materials and their bioactive surfaces by supercritical CO2.
abstract: The development of biomaterials endowed with bioactive features relies on a simultaneous insight into a proper terminal sterilization process. FDA recommendations on sterility of biomaterials are very strict: a sterility assurance level (SAL) of 10(-6) must be guaranteed for biomaterials to be used in human implants. In the present work, we have explored the potential of supercritical CO(2) (scCO(2)) in the presence of H(2)O(2) as a low-temperature sterilization process for thermoset materials and their bioactive surfaces. Different conditions allowing for terminal sterilization have been screened and a treatment time-amount of H(2)O(2) relationship proposed. The selected terminal sterilization conditions did not notably modify the mechanical properties of the thermoset nor of their fiber-reinforced composites. This was confirmed by μCT analyses performed prior to and after the treatment. On the contrary, terminal sterilization in the presence of H(2)O(2) induced a slight decrease in the surface hardness. The treatment of the thermoset material with scCO(2) led to a reduction in the residual unreacted monomers content, as determined by means of high performance liquid chromatography (HPLC) analyses. Finally, it was found that a thermoset coated with a polysaccharide layer containing silver nanoparticles maintained a very high antimicrobial efficacy even after the scCO(2)-based terminal sterilization.
authors.affiliation: Department of Life Sciences, University of Trieste, Trieste, Italy. idonati@units.it
authors.forename: Ivan
authors.initials: I
authors.lastname: Donati
authors.forename: Monica
authors.initials: M
authors.lastname: Benincasa
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Foulc
authors.forename: Gianluca
authors.initials: G
authors.lastname: Turco
authors.forename: Mila
authors.initials: M
authors.lastname: Toppazzini
authors.forename: Dario
authors.initials: D
authors.lastname: Solinas
authors.forename: Sara
authors.initials: S
authors.lastname: Spilimbergo
authors.forename: Ireneo
authors.initials: I
authors.lastname: Kikic
authors.forename: Sergio
authors.initials: S
authors.lastname: Paoletti
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry* / Q000494:pharmacology; D002245:Carbon Dioxide / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004305:Dose-Response Relationship, Drug; D006861:Hydrogen Peroxide / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry; D008826:Microbial Sensitivity Tests; D011092:Polyethylene Glycols / Q000737:chemistry* / Q000494:pharmacology; D011109:Polymethacrylic Acids / Q000737:chemistry* / Q000494:pharmacology; D011134:Polysaccharides / Q000737:chemistry; D012834:Silver / Q000737:chemistry; D013211:Staphylococcus aureus / Q000187:drug effects; D013329:Structure-Activity Relationship; D013499:Surface Properties; D013696:Temperature
chemical_list: D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D011109:Polymethacrylic Acids; D011134:Polysaccharides; D002245:Carbon Dioxide; C020946:triethylene glycol dimethacrylate; D012834:Silver; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; D006861:Hydrogen Peroxide