Fucoidan hydrogels photo-cross-linked with visible radiation as matrices for cell culture

Algae are abundant sources of bioactive components with extensive therapeutic properties, receiving much interest in recent years. The research on marine brown algae, namely one of its polysaccharide-fucoidan, has increased exponentially. Fucoidan is a sulfated cell-wall polysaccharide with several reported biological properties including anticancer, antivirus, anticoagulant, antioxidant and anti-inflammatory effects. In this study, fucoidan was functionalized by grafting methacrylic groups in the chain backbone, photo-cross-linkable under visible light to obtain biodegradable structures for tissue engineering. The functionalization reaction was carried out by concentrations (8 and 12%) of methacrylic anhydride (MA). The modified fucoidan (MFu) was characterized by FTIR and 1HNMR spectroscopy to confirm the functionalization. Further, modified fucoidan was photo-cross-linked under visible light and using superhydrophobic surfaces, to obtain spherical particles with controlled geometries benefiting from the high repellence of the surfaces. When using higher concentrations of MA, the particles were observed to exhibit a smaller average diameter. Moreover, the behavior of L929 mouse fibroblast-like cells was evaluated when cultured in contact with photo-cross-linked particles was investigated, being observed up to 14 days in culture. The photo-cross-linking of MFu under visible light enables thus the formation of particles here suggested as potentially relevant in a wide range of biomedical applications.ERDF: Atlantic Area Project 2011-1/164 MARMED and POCTEP Project 0687_NOVOMAR_1_P FP7: Project POLARIS (FP7-REGPOT_CT2012-316331) Portuguese Foundation for Science and Technology (FCT): project CarbPol_mu_Algae (EXPL/MAR-BIO/0165/2013) and scholarships (SFRH/BD/73172/2010, SFRH/BD/112139/2015, and SFRH/BPD/85790/2012, SFRH/BPD/112140/2015)