Comprehensive Appraisal of Graphene–Oxide Ratio in Porous Biopolymer Hybrids Targeting Bone-Tissue Regeneration

Abstract

The bone-tissue engineering (BTE) field is continuously growing due to a major need for bone substitutes in cases of serious traumas, when the bone tissue has reduced capacity for self-regeneration. So far, graphene oxide (GO)-reinforced natural materials provide satisfactory results for BTE, for both in vitro and in vivo conditions. In this study, we aimed to evaluate the biocompatibility of a new biocomposite consisting of chitosan and fish gelatin crosslinked with genipin and loaded with various concentrations of GO (0.5, 1, 2, 3 wt.%) for prospective BTE applications. Scaffold characterizations revealed a constant swelling degree and good resistance to enzyme degradation. The composites presented a porous structure with pores of similar size, thus mimicking the bone structure. In vitro biocompatibility assays demonstrated an overall beneficial interaction between preosteoblasts, and these particular composites, particularly with 0.5 wt.% GO, reinforced composition. Next, the materials were implanted subcutaneously in 6-week old CD1 mice for in vivo evaluation of biocompatibility and inflammatory activity. Immunohistochemical staining revealed maximal cell infiltration and minimal inflammatory reaction for fish gelatin/chitosan/genipin with 0.5 wt.% GO scaffold, thus demonstrating the best biocompatibility for this particular composition, confirming the in vitro results. This study revealed the potential use of fish gelatin/chitosan GO composites for further implementation in the BTE field.

Graphene–Oxide Porous Biopolymer Hybrids Enhance In Vitro Osteogenic Differentiation and Promote Ectopic Osteogenesis In Vivo

“…The fish gelatin/chitosan crosslinked with genipin and reinforced with different GO biopolymer scaffolds have been previously analyzed by our group for their good physico-chemical properties and biocompatibility [ 15 , 42 ]. The in vitro osteogenic potential analysis and the de novo bone-forming capacity in vivo was compared for three materials: i. GCs (to evaluate the baseline osteoinductivity of an unmodified hybrid substrate); ii.…”

“…The oxygen-containing functional groups found in the GO structure ensure a great interaction with cellular proteins, hence significantly contributing to cellular behavior [ 14 ] in terms of cell growth and viability. GO has turned out to be a reliable nano-component due to its biocompatibility, which has been addressed in several studies over the years [ 15 , 16 ].…”

“…In our previous studies, we developed a new scaffold composed of fish gelatin/chitosan crosslinked with genipin (GCsGp) and reinforced with various GO:biopolymer mass ratios [ 15 , 42 ]. Appertaining on preliminary results, including thorough biocompatibility, we concurred and highlighted that the macromolecule network best performs if reinforced with 0.5 wt.% GO.…”

Electrochemically derived nanographene oxide activates endothelial tip cells and promotes angiogenesis by binding endogenous lysophosphatidic acid

“…2 c; Fig. S2b in the supporting information); this concentration of NGO/GelMA was within the safe ratio for most cell types and from in vivo tissue engineering references [ 23 , 24 ]. Three-dimensional images of blood vessels in the defect regions were obtained using intravenous injection of rhodamine B and multiphoton laser scanning microscopy to offer more intuitive information.…”

Computed Tomography as a Characterization Tool for Engineered Scaffolds with Biomedical Applications

“…Apart from the visualization of internal morphology and quantitative analysis regarding pores' size, distribution, and interconnectivity, CT is often employed to evaluate phase distribution in a composite material [64,151]. When such analysis is performed, attention must be paid to the different X-ray adsorption abilities of the two components, which may lead to poor phase contrast.…”