Bioactive Gum Arabic/κ-Carrageenan-Incorporated Nano-Hydroxyapatite Nanocomposites and Their Relative Biological Functionalities in Bone Tissue Engineering

Abstract

The present frontiers of bone tissue engineering are being pushed by novel biomaterials that exhibit phenomenal biocompatibility and adequate mechanical strength. In this work, we fabricated a ternary system incorporating nano-hydroxyapatite (n-HA)/gum arabic (GA)/κ-carrageenan (κ-CG) with varying concentrations, i.e., 60/30/10 (CHG1), 60/20/20 (CHG2), and 60/10/30 (CHG3). A binary system with n-HA and GA was also prepared with a ratio of 60/40 (HG) and compared with the ternary system. A rapid mineralization of the apatite layer was observed for the ternary systems after incubation in simulated body fluid (SBF) for 15 days as corroborated by scanning electron microscopy (SEM). CHG2 exhibited the maximum apatite layer deposition. Further, the nanocomposites were physicochemically analyzed by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and mechanical testing. Their results revealed a substantial interaction among the components, appropriate crystallinity, and significantly enhanced compressive strength and modulus for the ternary nanocomposites. The greatest mechanical strength was achieved by the scaffold containing equal amounts of GA and κ-CG. The cytotoxicity was evaluated by culturing osteoblast-like MG63 cells, which exhibited the highest cell viability for the CHG2 nanocomposite system. It was further supported by confocal microscopy, which revealed the maximum cell proliferation for the CHG2 scaffold. In addition, enhanced antibacterial activity, protein adsorption, biodegradability, and osteogenic differentiation were observed for the ternary nanocomposites. Osteogenic gene markers, such as osteocalcin (OCN), osteonectin (ON), and osteopontin (OPN), were present in higher quantities in the CHG2 and CHG3 nanocomposites as confirmed by western blotting. These results substantiated the pertinence of n-HA-, GA-, and κ-CG-incorporated ternary systems to bone implant materials.

Fabrication of silver doped nano hydroxyapatite-carrageenan hydrogels for articular cartilage applications

“…This may be attributed to the presence of higher amount of CG in the hydrogels. It has been established that CG is responsible for higher Ca deposition because of its affinity to bind Ca that subsequently accelerate cell differentiation giving rise to new bone formation [17].…”

“…Furthermore, the gel strength has been found to be higher in case of less sulfate concentration in carrageenan and the least ester sulfate is available in κ-carrageenan that can be most appropriate for applications in bone scaffolds. In addition, GAGs which are the constituent of bone and cartilage of humans have been shown to have structurally analogous to κ-carrageenan (κ-CG) [17].…”

A novel classification of bone graft materials

“…Kappa‐carrageenan is a gelling agent processed from a natural sea‐weed source. They have been studied in vitro, showing promising levels of osteogenesis and cytocompatibility 178,179 . Injectable composites made of tricalcium phosphate substituted with magnesium mixed with calcium sulfate hemihydrate particles, which had self‐setting ability, were tested in vivo in beagle condyle defects exhibiting new bone formation, biodegradability, and biocompatibility 180 .…”

Carrageenan: Drug Delivery Systems and Other Biomedical Applications

“…Comparative assessment of morphological, physicochemical, and biological studies revealed that ternary systems possess superior biocompatibility, protein adsorption and osteogenic protein expression as compared to the binary system formed by nHA and GA. Therefore, the authors concluded that the incorporation of kappa -CG to the ternary system outperforms the binary system collectively in terms of bioactivity with the maximal activity shown by the nanocomposite formed by nHA/GA/ kappa -CG in a ratio of 60/20/20 [ 192 ].…”