Surface modification of collagen-based artificial cornea for reduced endothelialization

Our objective was to develop collagen-based hydrogels as tissue substitutes for corneal transplantation. The design of the full-thickness corneal grafts includes prevention of cell migration onto the posterior surface of the implants, using a plasma-assisted surface modification technique. Briefly, the hydrogel materials were subjected to ammonia plasma functionalization followed by grafting of alginate macromolecules to the target surface. The treated materials surfaces showed observable decreases in endothelial cell attachment. The decrease in cell attachment and adhesion was dependant upon the concentration of alginate and plasma radio frequency (RF) power. High concentrations of alginate 5% (w/v) and high RF power of 100 W produced surfaces with minimal cell attachment. The plasma-alginate treatment did not adversely affect the optical or swelling properties of the constructs. Contact angle measurement analysis revealed that the posterior surface hydrophilicity significantly increased after the treatment. The grafting of alginate to the implants surfaces was confirmed by fourier transform infrared spectroscopy. Both of the untreated and alginate grafted corneal materials were found to be superior to human cornea in optical and swelling properties.