Innovative methodology for marine collagen-chitosan-fucoidan hydrogels production, tailoring rheological properties towards biomedical application

Accepted ManuscriptMarine polymers such as collagen, chitosan, and fucoidan can be combined to form ionic-linked hydrogel networks towards applications in tissue engineering (TE). The use of greener approaches (as determined by green metrics â E-factor), including the absence of external chemical cross-linking agents, has advantages regarding the potential cytotoxicity. By tailoring the formulation of such an ionic-linked hydrogel, it is possible to fine-tune scaffold biofunctionality. In this study, a comparative study of composite hydrogels was accomplished, seeking to understand the correlation between polymer characteristics and physical behaviour to develop the applicability of this technology in soft-to-hard TE. Parameters such as polymer concentration, molecular weight, polymer-biomaterials bonds, biomaterial structural architecture, pore size, and mechanical rheological properties were directly correlated to the hydrogelâ s formulation. The results highlight that the formulation with greatest potential was the 3-component hydrogel (H12, followed by H10, H11), due to its superior mechanical properties, making it suitable for cartilage TE. This research offers a valuable perspective on hydrogel formulation and a new processing methodology, as well as how tailoring the hydrogel composition influences mechanical behaviour to support selecting the best composition for tissue engineering applications.The authors would like to acknowledge to Portuguese Foundation of Science and Technology (FCT) for a Ph.D. fellowship (D. N. Carvalho) under the scope of the doctoral program Tissue Engineering, Regenerative Medicine and Stem Cells, ref. PD/BD/143044/2018, and for Postdoctoral fellowship (C. Goncalves), ref. SFRH/BPD/94277/2013. This work has been partially funded by ERDF under the scope of the Atlantic Area Program through project EAPA_151/2016 (BLUEHUMAN). The authors also thank Jellagen Ltd (UK) for the provision of purified jellyfish collagen. The authors would also like to acknowledge Dr Julio Maroto from the Fundacion CETMAR and Roi Vilela from PESCANOVA S.A, Spain, for the kind offer of squid pens, and to Lara L. Reys for the initial chitosan extraction process