The invention relates to an innovative method for the prodn. of crosslinked polysaccharides which have the characteristic of maintaining the shape of the original solid matrix, and are therefore called shape-memory polysaccharides. The process according to the invention involves crosslinking at least one water-sol. polysaccharide, in particular hyaluronic acid and hyaluronans, chondroitin, chondroitin sulfate and chitosan, with at least one polyfunctional epoxy crosslinking agent, operating in a biphasic system consisting of the polysaccharide matrix, which always remains in the solid state throughout the crosslinking process, and a non-solvent system for the polysaccharide. The materials obtained by the process according to the invention are insol. in aq. systems and maintain their original shape after hydration. The process according to the invention is particularly important in the prepn. of crosslinked shape-memory polysaccharides for clin. applications and in the field of aesthetic medicine. For example, hyaluronic acid (HA) was crosslinked with 1,4-butanediol diglycidyl ether (BDDE) crosslinking agent in the presence of benzyl tri-Me ammonium hydroxide (TMBAH) using the water-acetone solvent system. The reaction was stopped by adding concd. H3PO4 until neutralization. The reaction yields of the crosslinked HA was dependent on the amt. of water in the reaction mixt., including the water present in the TMBAH: for the solvent mixts. comprising acetone-water at 79.32:10.0 and 62.62:26.7 mL/mL, resp., the yields of the crosslinked shape-memory water-insol. HA was 43.4% and 79.4%, resp. The material obtained was cytocompatible.
Shape-memory crosslinked polysaccharides for biomaterials
Mario De Rosa;Annalisa La Gatta;Chiara Schiraldi
2013
Abstract
The invention relates to an innovative method for the prodn. of crosslinked polysaccharides which have the characteristic of maintaining the shape of the original solid matrix, and are therefore called shape-memory polysaccharides. The process according to the invention involves crosslinking at least one water-sol. polysaccharide, in particular hyaluronic acid and hyaluronans, chondroitin, chondroitin sulfate and chitosan, with at least one polyfunctional epoxy crosslinking agent, operating in a biphasic system consisting of the polysaccharide matrix, which always remains in the solid state throughout the crosslinking process, and a non-solvent system for the polysaccharide. The materials obtained by the process according to the invention are insol. in aq. systems and maintain their original shape after hydration. The process according to the invention is particularly important in the prepn. of crosslinked shape-memory polysaccharides for clin. applications and in the field of aesthetic medicine. For example, hyaluronic acid (HA) was crosslinked with 1,4-butanediol diglycidyl ether (BDDE) crosslinking agent in the presence of benzyl tri-Me ammonium hydroxide (TMBAH) using the water-acetone solvent system. The reaction was stopped by adding concd. H3PO4 until neutralization. The reaction yields of the crosslinked HA was dependent on the amt. of water in the reaction mixt., including the water present in the TMBAH: for the solvent mixts. comprising acetone-water at 79.32:10.0 and 62.62:26.7 mL/mL, resp., the yields of the crosslinked shape-memory water-insol. HA was 43.4% and 79.4%, resp. The material obtained was cytocompatible.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
