Synthesis and physical-chemical characterization of a cotton-wool-like nanofibers biopolymer of graphene oxide

• Grant number: 18/15145-8
• Support Opportunities: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): March 01, 2020
• Effective date (End): June 30, 2023
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Rafael Francisco Lia Mondelli
• Grantee: Marilia Mattar de Amoêdo Campos Velo
• Host Institution: Faculdade de Odontologia de Bauru (FOB). Universidade de São Paulo (USP). Bauru , SP, Brazil

Abstract

The high incidence of resin composite restorations replacements' highlights the requirement of new restorative materials development. The last decades have shown a rapid and growing advance in nanomaterials. The discovery of graphene is considered to be one of the major forces that boosted nanotechnology thus generating great interest from scientists around the world. In the field of tissue engineering, new hybrid biomaterials composed of organic and inorganic phases have been researched as a grouping of reinforced physical-chemical properties. The doping process of bioactive hybrids in the configuration of nanofibers (cotton wool-like) with graphene oxide represents an innovative feature of this research project, since it presents similar color to dental structures and can be used in restorative materials with potential for increase the longevity of resin composite restorations with satisfactory optical properties. Firstly, a resin matrix will be prepared (49.5% BisGMA, 49.5% TEGDMA, 2- dimethacrylate 0.8% and camphorquinone 0.2%) and hybrid nanofibers (200 nm) of Poly (lactide acid) + Silica (1%, 2%, 4%, 8% and 12%) doped with functionalized graphene oxide (1%, 2% and 5%) will be incorporated. The nanofibers will be characterized regarding their physical-chemical properties, which involves morphology aspects, degree of thermic degradability and composition. Afterward, the developed biopolymer will be analyzed by FTIR (n=3), 3-point flexural strength (n=10), modulus of elasticity (n=10), SEM images (n=3) and Knoop hardness (n=5). Lastly, in order to approach this study of that found on in vivo conditions, an in vitro Simulated Body Fluid test will be performed in order to determine the apatite formation of the specimens, after immersion in the saturated solution at 37°C in an incubator and evaluated by FTIR and X-ray diffraction after (1,12,24,72,168 and 336 hs) of immersion. The quantitative data will be submitted to two-way ANOVA and Tukeys' test (p<0.05). (AU)