Physical and chemical effect of an electrospun nanocomposite of gelatin/polyvinyl alcohol loaded with heparin

The field of materials has focused on developing fibrillar, porous, laminar, or hybrid structures for applications in the biochemical, biophysical, and biological areas at the micro and nanoscale. Said biomaterials can be of protein and synthetic origin, seeking to imitate the morphological characteristics of native tissues. Fibrillar scaffolds composed of polyvinyl alcohol and gelatin with heparin incorporation at concentrations of 5 % and 20 % v/v were developed by the electrospinning technique. The scaffolds were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, contact angle, thermogravimetric analysis, and mechanical tests. The MTT assay and cell adhesion were carried out in interaction with an in vitro model of RL-14 cardiomyocytes.

It was found that the diameters of the fibers depended on the decrease in the proportion of gelatine and the increase in the concentration of heparin, responding to a hybrid morphology with diameters from 176 nm to 166 nm. Likewise, it was evidenced that the cross-linking effect using glutaraldehyde and ethanol increased the resistance to dissolution in aqueous media, due to the modifications induced in the secondary structures of the protein. On the other hand, it was found that as the concentration of heparin in the electrospun membranes increased, viability and cellular adhesion decreased. In addition, it was found that the incorporation of heparin induces a decrease in the stiffness and elasticity of the scaffold, and the cell viability is dependent on the concentration of the active principle. Therefore, scaffolds could be applied as a potential biomaterial in tissue engineering.