Freeze-drying synthesis, characterization and in vitro bioactivity of chitosan/graphene oxide/hydroxyapatite nanocomposite

Abstract

Polycrystalline and dispersed hydroxyapatite (HAP) nanoparticles were successfully prepared via a simple precipitation method with the aid of a new capping agent based on Schiff base compounds. After that, a composite of chitosan (CT), graphene oxide (GO) and HAP nanoparticles was synthesized by a freezedrying method. The as-produced Schiff base, HAP nanoparticles, and CT/GO/HAP nanocomposite were analysed by several techniques including FTIR, SEM, HR-TEM, and XRD. In addition, the in vitro bioactivity of HAP nanoparticles and the CT/GO/HAP nanocomposite was evaluated by soaking them in simulated body fluid (SBF). By monitoring the changes of chemical composition of the SBF solutions, it was concluded that more Ca and P ions were released from the CT/GO/HAP nanocomposite compared to the pure HAP nanoparticles, indicating a high bioactivity of the nanocomposite. The SEM images showed that the formation and growth of apatite on the surfaces of the products increased after immersion for 14 days in SBF.

Novel porous graphene oxide and hydroxyapatite nanosheets-reinforced sodium alginate hybrid nanocomposites for medical applications

“…The TG curve of GO is typical and was reported by other researchers such as Mohandes [45]. HAp is thermally stable [45,46], and the slight weight loss can be ascribed to the decomposition of glucosamine grafting layer. The TG curves of HAp20/SA and GO/HAp/SA nanocomposites bear resemblance to neat SA since SA is the major component in these nanocomposites.…”

Graphene and graphene oxide as nanomaterials for medicine and biology application

“…HAp, a commonly used material, has been combined with graphene for enhanced capabilities [113,114]. The addition of chitosan or PEG to HAp/GO nanocomposite can release the considerably high amount of calcium and phosphorus ions as compared to only HAp [114,115]. Several improvements have been observed in the mechanical and physical properties when graphene is combined with HAp.…”

Chitosan nanocomposites based on distinct inorganic fillers for biomedical applications

“…This kind of structure presents a swelling behavior ideal for wound dressing applications, it is biodegradable and has hemostatic potential. [119] Mohandes and Salavati-Niasari,[120] using the same processing methodology, were able to synthetize a composite of CHI, GO and HA NPs, and studied its bioactivity, revealing a higher Ca and P ions release, after 14 days, than HA by itself. CHI-gelatin/MMT-HA scaffolds were prepared through freeze drying showing a nanoscale architecture with well-interconnected pores, with a mean pore size of 250 μm, similar to natural bone.…”