Cross-linked soy protein as material for biodegradable films: Synthesis, characterization and biodegradation

A. GONZÁLEZ; M. STRUMIA; C. I. ALVAREZ IGARZABAL

Congreso; Segundo Taller de Órganos artificiales, biomateriales e Ingeniería de Tejidos (OBI); 2011

The modification of soy protein isolate (SPI) with different amounts of a naturally and non-cytotoxic cross-linking agent (genipin, Gen) and glycerol used as plasticizer was carried out in this work. In colony-forming assays, the proliferative capacity of cells after being exposed to Gen is approximately 5000 times greater than that of cells exposed to glutaraldehyde. Different films were prepared by casting from heated and alkaline aqueous solution of SPI, glycerol and Gen and then dried in an oven. Total soluble matter, water vapor permeability and mechanical properties were improved by adding small amounts of Gen. These properties were not significantly affected (P≥0.05) by additions exceeding 2.5% (w/w of SPI). The opacity and cross-linking degree were linearly increased with the addition of Gen, whereas the swelling ratios in water were decreased. All the films were submitted to degradation under indoor soil burial conditions and the weight loss of the films was measured at different times. This study revealed that the film biodegradation time can be controlled or modified from at least 14 to 33 days. The tests performed showed the potential of Gen to improve the SPI film properties. Therefore, the possibility of employing such new films as artificial tissue for biomedical applications was raised.