AUTHOR=Dudik Olesia , Amorim Sara , Xavier Joana R. , Rapp Hans Tore , Silva Tiago H. , Pires Ricardo A. , Reis Rui L. 

TITLE=Bioactivity of Biosilica Obtained From North Atlantic Deep-Sea Sponges

JOURNAL=Frontiers in Marine Science

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2021.637810

DOI=10.3389/fmars.2021.637810

ISSN=2296-7745

ABSTRACT=<p>Demosponges are a well-known source of a plethora of bioactive compounds. In particular, they are able to form a skeleton by direct deposition of silica in a process catalyzed by silicatein. Herein, we isolated biosilicas from five different Atlantic deep-sea sponges <italic>Geodia atlantica</italic> (GA), <italic>Geodia barretti</italic> (GB), <italic>Stelletta normani</italic> (SN), <italic>Axinella infundibuliformis</italic> (AI), and <italic>Phakellia ventilabrum</italic> (PV) to explore the bioactivity and osteogenic capacity of its silica-based materials. We chemically characterized the isolated biosilicas and evaluated them for their bioactivity to deposit Ca and P on their surface (by immersion in simulated body fluid, SBF). GB-, SN-, AI-, and PV-based biosilicas did not generate a stable calcium phosphate (CaP) layer over time in the presence of SBF, however, the GA-derived one was able to form a CaP surface layer (at a Ca/P ratio of ∼1.7, similar to the one observed for hydroxyapatite), that was stable during the 28 days of testing. In addition, no cytotoxicity toward L929 and SaOs2 cells was observed for the GA-based biosilica up to a concentration of 10 mg/mL. Overall, the GA-based biosilica presents the characteristics to be used in the development of biomaterials for bone tissue engineering (BTE).</p>