Purified alginate: biocompatibility and cytotoxic studies

TORRES ML; OBERTI TG; DELLATORRE FG; A.M. CORTIZO; FERNANDEZ JM

Congreso; 2º Reunión Conjunta de Sociedades de BioCiencias?; 2017

Alginate is a natural polysaccharide obtained from brown seaweed. Due to many attractive features such as good biocompatibility, low toxicity as well as ease of hydrogel formation with divalent cations, it has been widely used in a variety of biomedical application, such as medical delivery and tissue engineering. These applications re-quired highly purified materials. However the alginate extracted from brown seaweed and commercial alginate contain a large number of impurities, such as proteins, polyphenols and endotoxins, which might lead to an intense host immune reaction and reduce the bio-compatibility of alginate. The brown algae, Undaria pinnatifida, na-tive China is an invasive species which was introduced worldwide in different coasts, including the one of Puerto Madryn (Argentina). In this study, we compare U. pinnatifida ?s sodium alginate extracted from two different tissue sources (Stem Alginate, SA, and Leaf Algi-nate, LA) with the commercial salt (CA, Sigma) and its purified (PSA, PLA, PCA) using a method based on chloroform/butanol. Bone Ma-rrow Progenitor Cells (BMPC) were grown in an osteogenic medium in presence of alginate during 14 days. Biocompatibility was evalua-ted by measuring the activity of the enzyme alkaline phosphatase (ALP) and production of collagen type 1 (COLt1) as parameter of osteogenic differentiation. Cell citotoxicity was evaluated measuring nitric oxide (NO) liberation and viability was assessed using MTT method during 48hs in murine macrophage-like cell RAW 264.7. Results showed, in all cases, that unpurified samples induce a de -crease in cellular viability (p