Silk fibroin/gelatin blend films crosslinked with enzymes for biomedical applications.

Microbial transglutaminase (mTG) and mushroom tyrosinase (MT) are used to crosslink B. mori silk fibroin/gelatin (SF/G) films. Crosslinked and uncrosslinked SF/G films show no phase separation. The thermal behavior and the conformational structure of SF/G films are strongly affected by blending and enzymatic treatment. Formation of high thermally stable crosslinked macromolecular species is observed, suggesting the occurrence of strong intermolecular interactions between the two polymers as confirmed by FT-Raman spectroscopy. Preliminary in vitro tests show that MT-crosslinked blends with G amounts ≥40% and mTG-crosslinked SF/G 60/40 films support C2C12 cardiomyocyte adhesion and proliferation.