title: Comparative facile methods for preparing graphene oxide-hydroxyapatite for bone tissue engineering.
abstract: Motivated by the success of using graphene oxide (GO) as a nanofiller of composites, there is a drive to search for this new kind of carbon material as a bioactive component in ceramic materials. In the present study, biomineralized GO was prepared by two different approaches, represented by in situ sol-gel synthesis and biomimetic treatment. It was found that in the biocomposites obtained by the sol-gel approach, the spindle-like hydroxyapatite nanoparticles, with a diameter of ca. 5 ± 0.37 nm and a length of ca. 70 ± 2.5 nm, were presented randomly and strongly on the surface. The oxygen-containing functional groups, such as hydroxyl and carbonyl, present on the basal plane and edges of the GO sheets, play an important role in anchoring calcium ions, as demonstrated by FT-IR and TEM investigations. A different result was obtained for biocomposites after biomimetic treatment: an amorphous calcium phosphate on GO sheet was observed after 5 days of treatment. These different approaches resulted in a diverse effect on the proliferation and differentiation of osteogenic mesenchymal stem cells. In fact, in biocomposites prepared by the sol-gel approach the expression of an early marker of osteogenic differentiation, ALP, increases with the amount of GO in the first days of cell culture. Meanwhile, biomimetic materials sustain cell viability and proliferation, even if the expression of alkaline phosphatase activity in a basal medium is delayed. These findings may provide new prospects for utilizing GO-based hydroxyapatite biocomposites in bone repair, bone augmentation and coating of biomedical implants and broaden the application of GO sheets in biological areas. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Institute of Polymers, Composites and Biomaterials, National Research Council of Italy, Naples, Italy.
authors.forename: M G
authors.identifier: 0000-0002-0516-4181
authors.initials: MG
authors.lastname: Raucci
authors.affiliation: Institute of Polymers, Composites and Biomaterials, National Research Council of Italy, Naples, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Giugliano
authors.affiliation: Institute of Polymers, Composites and Biomaterials, National Research Council of Italy, Naples, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Longo
authors.affiliation: Institute of Polymers, Composites and Biomaterials, National Research Council of Italy, Naples, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Zeppetelli
authors.affiliation: Institute of Polymers, Composites and Biomaterials, National Research Council of Italy, Naples, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Carotenuto
authors.affiliation: Department of Chemicals Science and Materials Technology, National Research Council of Italy (DSCTM-CNR), Rome, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Ambrosio
mesh_terms: D001842:Bone and Bones / Q000166:cytology / Q000378:metabolism*; D002454:Cell Differentiation; D017886:Durapatite / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D053758:Nanoparticles / Q000737:chemistry*; D023822:Tissue Engineering
chemical_list: D006108:Graphite; D017886:Durapatite
keywords: biomineralization; bone repair; graphene oxide; human mesenchymal stem cells; hydroxyapatite; sol-gel