Silicate-doped nano-hydroxyapatite/graphene oxide composite reinforced fibrous scaffolds for bone tissue engineering

Abstract

In this study, novel graphene oxide-incorporated silicate-doped nano-hydroxyapatite composites were prepared and their potential use for bone tissue engineering was investigated by developing an electrospun poly(ε-caprolactone) scaffold. Nanocomposite groups were synthesized to have two different ratios of graphene oxide (2 and 4 wt%) to evaluate the effect of graphene oxide incorporation and groups with different silicate-doped nano-hydroxyapatite content was prepared to investigate optimum concentrations of both silicate-doped nano-hydroxyapatite and graphene oxide. Three-dimensional poly(ε-caprolactone) scaffolds were prepared by wet electrospinning and reinforced with silicate-doped nano-hydroxyapatite/graphene oxide nanocomposite groups to improve bone regeneration potency. Microstructural and chemical characteristics of the scaffolds were investigated by X-ray diffraction, Fourier transform infrared spectroscope and scanning electron microscopy techniques. Protein adsorption and desorption on material surfaces were studied using fetal bovine serum. Presence of graphene oxide in the scaffold, dramatically increased the protein adsorption with decreased desorption. In vitro biocompatibility studies were conducted using human osteosarcoma cell line (Saos-2). Electrospun scaffold group that was prepared with effective concentrations of silicate-doped nano-hydroxyapatite and graphene oxide particles (poly(ε-caprolactone) - 10% silicate-doped nano-hydroxyapatite - 4% graphene oxide) showed improved adhesion, spreading, proliferation and alkaline phosphatase activity compared to other scaffold groups.

Use of Nanoparticles in Tissue Engineering and Regenerative Medicine

“…Combination of HAp with various from of carriers such as electrospun fibers (Cai et al, 2017; Samadian et al, 2018), porous scaffolds (Guo M. et al, 2018), and hydrogels (Ghosh et al, 2017) have been reported for preparation of nanocomposite materials to modulate the desired cellular activities. Recently, graphene oxide-incorporated silicate-doped nano-HAp composites have been used for reinforcement of fibrous scaffolds of PCL produced by wet electrospinning for bone tissue engineering (Dalgic et al, 2018). Silicate-doped nano-hydroxyapatite (10%)—graphene oxide (4%) group was reported to enhance the adhesion, spreading, proliferation and ALP activity of Saos-2 cells compared to other scaffold groups.…”

<p>Applications of Graphene and Its Derivatives in Bone Repair: Advantages for Promoting Bone Formation and Providing Real-Time Detection, Challenges and Future Prospects</p>

“… 11 , 12 It has been demonstrated that GDs can provide sufficient mechanical reinforcement to bone repair scaffolds, 13 bring desired electrical stimulation to cell osteogenic activities and bone formation, 14 and be conducive to the adsorption of active substances. 15 Moreover, the hexagonal single-layer carbon atomic structure of graphene makes strong structural stability, which is not easy to be destroyed during complex scaffold preparation process with organic solvents and at the implantation sites under physiological environments. 16 But, pure graphene particles are difficult to form a 3D scaffold themselves and have poor fluidity to inject into the body, so they have been normally compounded with other substrates to use in bone repair.…”

Osteogenic Potential of Graphene in Bone Tissue Engineering Scaffolds

“…Ali et al [73] prepared a novel graphene oxide incorporated silicate-doped nano hydroxyapatite composite scaffold for bone tissue engineering. Electrospun PCL scaffolds were fabricated and the Graphene oxide-Hydroxyapatites nano composite were reinforced within the scaffolds.…”

“…The scaffolds were biocompatible when treated with human osteosarcoma cell lines. The scaffolds showed good adhesion, proliferation of cell lines, and increased ALP activity [73]. …”