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.

In situ syntheses of hydroxyapatite‐grafted graphene oxide composites

“…Especially for Synthesis C, this is almost completely absent even in composites that have a greater amount of GO. This is probably due to the loss of the crystallographic order after ultrasonication and to a greater intercalation of the nano HAp particles between the graphenic planes (Li et al, ; Raucci et al, ).…”

“…In the GO–HAp composites, HAp is strongly and uniformly intercalated with the GO sheets that act as a nucleation site. Compared with the HAp, the prepared GO–HAp nanocomposites displayed an increased solubility in water with higher GO percentages due probably to the lower crystallinity of HAp composites with intercalated GO sheets (Raucci et al, ).…”

Starch Derived Nanosized Graphene Oxide Functionalized Bioactive Porous Starch Scaffolds

“…One of the interesting functions of GO among all its merits is that it can promote hydroxyapatite (HAP) mineralization due to its polar groups . In some HAP‐containing composite materials, the presence of GO improved the bioactivity and also induced an osteogenic differentiation through osteoblast phenotype of Human Mesenchymal Stem Cells (hMSCs) . This makes GO suitable for utilization in bone tissue engineering.…”

“…[29][30][31] In some HAP-containing composite materials, the presence of GO improved the bioactivity and also induced an osteogenic differentiation through osteoblast phenotype of Human Mesenchymal Stem Cells (hMSCs). [32] This makes GO suitable for utilization in bone tissue engineering. By incorporating GO, scaffolds with improved osteogenic bioactivity can be obtained.…”

Gelatin/nano‐hydroxyapatite hydrogel scaffold prepared by sol‐gel technology as filler to repair bone defects

“…) demonstrated that the HA particles were in a typical spindle‐like shape with a diameter of about 5.0 ± 0.4 nm and a length of around 20.0 ± 2.5 nm. These sizes are smaller than hydroxyapatite nanoparticles obtained by the same process and reported in our previous work . This effect may be because, these nanoparticles (B_HA 10 , B_HA 20 ) are oriented with their c ‐axis parallel to the gelatin axis and showed a smaller sizes due to the presence of gelatin that probably reduces the crystals growth …”