Commercial and extracted sodium alginate analysis after purification for bone tissue engineering application

TORRES MARÍA LUZ; FERNÁNDEZ, JUAN MANUEL; DELLATORRE, FERNANDO G.; CORTIZO, ANA MARÍA; OBERTI, TAMARA GISELA

Mar del Plata

Otro; LXI REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE INVESTIGACIÓN CLÍNICA; 2016

Sociedad Argentina de Inmunología

Alginate is a natural, water-soluble, polysaccharide obtained from brown algae consisting of β-D-mannuronate(M) and α-L- guluronate(G) residues (1→4). 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 required highly purified materials. However the alginate extracted from brown seaweed and commercial alginate contain a large number of impurities, such as proteins and polyphenols, which might lead to an intense host immune reaction and reduce the biocompatibility of alginate. The brown algae, Undaria pinnatifida, native from Japan, China and Korea is a powerful invasive species which was introduced worldwide in different coasts, and currently is distributed along a vast part of the Argentine coast. Sodium alginate can be obtained from this seaweed using and extraction process based on successive treatments with acid an alkaline solutions. In this study, we compare sodium alginate extracted from U. pinnatifida?s frond (blade and stem) tissue with the commercial salt (Sigma Aldrich) and its derivates after a purification method based on chloroform/butanol. The results showed that the purification procedure is necessary and effective to reduce protein content. Total protein measurement was performed using the method of Bradford. Neither de raw material nor the purified one showed significant amount of polyphenols after a determination using a spectrofluorimeter. Assay realized with an Ostwald viscosimeter showed that intrinsic viscosities of the purified samples were lower compared with the raw material. Samples characterization was perform by FTIR and TGA analysis. In conclusion, purified sodium alginate materials present a reduction of contamination by using a simple method that might generate a better biocompatibility than the unpurified ones (extracted and commercial).