Fabrication of oxidized alginate (ADA)/ gelatin (GEL) microcapsules incorporating Cu doped mesoporous bioactive glass nanoparticles (MBGNs) for soft tissue engineering applications

Abstract text (incl. figure legends and references)

Microcapsules (< 500 μm) encapsulated with cells using biodegradable and biocompatible hydrogels based on crosslinked alginate dialdehyde (ADA) and gelatin (GEL) are interesting candidates to fabricate tissue-engineered organs as well as for the regeneration of damaged tissues [1], due to their high porosity facilitating oxygen and nutrition supply [2]. The aim of this research is to fabricate ADA by periodate oxidation of alginate which facilitates crosslinking with gelatin through Schiff's base formation between the free amino groups of gelatin and the available aldehyde groups of ADA in 1:1 proportion [2]. The fabricated microcapsules were incorporated with Cu-doped mesoporous bioactive glass nanoparticles (Cu-MBGNs) prepared by the sol-gel method to promote angiogenesis. The swelling ratio and degradability of ADA–GEL microcapsules were significantly decreased with the increase of Cu-MBGN concentration due to the presence of the ceramic material. ADA-GEL microcapsules showed spherical morphology and successful incorporation of Cu-MBGNs, as evaluated by SEM. The cellular viability of fabricated ADA-GEL microcapsules increased with the addition of Cu-MBGNs, which was characterized using the NIH3T3 fibroblast cell line. In conclusion, ADA-GEL microcapsules incorporating Cu-MBGNs are biocompatible and biodegradable and exhibit intrinsic vascularization potential which makes them ideal candidates for soft tissue engineering applications.

References:

[1] F. F. Cai, S. Heid, and A. R. Boccaccini, "Potential of Laponite® incorporated oxidized alginate–gelatin (ADA-GEL) composite hydrogels for extrusion-based 3D printing," J. Biomed. Mater. Res. - Part B Appl. Biomater., vol. 109, no. 8, pp. 1090–1104, 2021.

[2] B. Sarker et al., "Fabrication of alginate-gelatin crosslinked hydrogel microcapsules and evaluation of the microstructure and physico-chemical properties," J. Mater. Chem. B, vol. 2, no. 11, pp. 1470–1482, 2014.