SIMULATION OF NOVEL SOY PROTEIN-BASED SYSTEMS FOR TISSUE REGENERATION APPLICATIONS

In the present research molecular modeling methods were used to study soy protein-gelatin and soy protein_alginate systems. The soy protein-based systems are novel porous blends, which were recently developed as potential scaffolds for tissue engineering applications. Gelatin (protein), and alginate (polysaccharides) were chemically cross-linked to soy protein isolates (SPI) using the cross-linking agents carbodiimide (EDC) or glyoxal, in order to obtain a porous 3D network.

The aim of the present study is to apply computational tools to estimate the crosslinking degree and compare the degradation rate of soy protein conjugates with gelatin or alginate.

Soy protein 3D structure was obtained from the Protein Data Bank (PDB). Alginate and gelatin structures were built using the builder tool of the molecular modeling package Material Studio 7.0. Simulation cubic boxes were constructed and subjected to dynamic simulation. The resulted dynamic trajectories were analyzed and several properties were calculated to estimate intermolecular interactions.

According to the results, alginate mixes much better with the crosslinking agent glyoxal than with EDC and therefor it is expected that a higher degree of crosslinking will be obtained with glyoxal for the soy protein-alginate system.

It was found that strong ionic interactions are formed between alginate chains in the soy protein_alginate conjugate, which makes it difficult for the water molecules to penetrate in between the chains. However, the gelatin chains in the soy protein_gelatin conjugate are more accessible to the water molecules. These results might account for the experimental observation that the soy protein_gelatin conjugate degrades faster than soy protein_alginate.