"Solvent/non-solvent" treatment as a method for non-covalent immobilization of gelatin on the surface of poly(L-lactic acid) electrospun scaffolds

In the present study, we report a simple and efficient method of gelatin immobilization on the surface of PLA electrospun fibers using pre-treatment with a mixture of toluene and ethanol allowing to form swelled surface layer followed by gelatin adsorption from its solution in PBS. Our results demonstrate that gelatin immobilization leads to a decrease in the water contact angle from 120 degrees to 0 degrees, enhances scaffold strength up to 50%, and doubles the number of adhered cells and their average area. We observed that the maximum amount of gelatin (0.07 +/- 0.01 mg per cm(3) of the scaffold) was immobilized during the first five minutes of exposure to the gelatin solution. Modified scaffolds demonstrated increased strength.