Fabrication of ۳D Bioprinted Scaffold with BiohybridAalginate Dialdehyde /Bone Extracellular Matrix for BoneTissue Engineering

Objective: The right combination of s tem cells and reasonablebiocompatible materials helps to improve bone regeneration.Bone extracellular matrix (ECM)-derived hydrogels have beenextensively used as a bioactive matrix to expedite the functional regeneration of bone tissue, but low mechanical s trength andrapid degradation limit the broad utilization of ECM for clinicalapplications. Here, we present biohybrid hydrogel based ondemineralized and decellularized human bone matrix (DBM)and alginate dialdehyde (AD) for bone tissue engineering.Materials and Methods: The alginate was partially oxidizedwith an oxidation degree of ۵% and the resulting AD wascross-linked by calcium carbonate. Also, AD aldehyde groupsreacted with DBM amine groups through Schiff-base reaction.To determine whether the bio-ink was printable, AD hydrogelwith different concentrations of DBM were printed by a threedimensional(۳D) bioprinter.Results: Bio-ink viscosity increased with increasing DBM concentrationand the hydrogels composed of ۸% w/v AD and ۲%w/v DBM showed acceptable printability. Moreover, the developedbio-ink containing DBM showed a suitable gelation timeand tensile Young's modulus. Cytocompatibility analysis of thebiohybrid hydrogel was conducted by MTT assay using placenta-derived mesenchymal s tem cells (P-MSCs). The resultsshowed that cell growth increased significantly with increasingDBM. Hydrogel with ۴% w/v concentration of DBM demonstrated higher cell viability compared with the other samples.The hydrogel containing ۲% DBM also showed acceptable celladhesion and growth.Conclusion: Overall, according to printability and biocompatibilityresults, hydrogel with ۸% w/v AD and ۲% w/v DBMmay be considered as the optimal candidate as bio-ink to beapplied for further s tudies in ۳D bioprinting for bone tissue engineering.The bio-ink with the above-mentioned compositionmay provide an appropriate niche for the migration and differentiationof MSCs.

کلیدواژه ها:

Alginate Dialdehyde ، Bioink ، Decellularized HumanBone Matrix ، Placenta-Derived Mesenchymal S tem Cells