Polymeric microcapsules poduction from sodium alginic acid for cell therapy

Abstract

Development of polymeric materials has been increasingly emphasized in Biomedicine. Here, we evaluate the use of microcapsules made of Biodritin®, a biocompatible polymer compound which contains sodium alginic acid, a natural polymer extracted from algae, and Cis-Chondroitin sulfate, a glycosaminoglycan from the extracellular matrix. Gelation of this polymer into microcapsules is achieved by dropping the compound into BaCl2 or CaCl2 gelling solutions. A functional microcapsule is dependent on its permeability, mechanical stability, immunoisolation capacity and biocompatibility. The mechanical stability of Biodritin-barium and Biodritin-calcium microcapsules was investigated after rotational stress upon in vitro culture and in vivo implantation. Viability studies of encapsulated cells were also performed to assess other functional parameters of the microcapsules. When subject to rotational stress, Biodritin-barium microcapsules exhibited breaks, whereas the Biodritin-calcium microcapsules did not. Both kinds of Biodritin® microcapsules proved to be mechanically resistant in in vitro and in vivo studies. However, the Biodritin-calcium material was found to be more elastic while the Biodritin-barium microcapsules displayed a more plastic behavior. These properties seem to be determinant for viability of the encapsulated cell’s, since the Biodritin-calcium microcapsules presented more viable cells than the Biodritin-barium microcapsules.

Keywords

• biomaterials
• alginate
• microcapsules
• cell therapy