UVA/riboflavin induced collagen cross-linking has been utilized for the treatment of keratoconus. The aim of the present study is to evaluate the influence of UVA/riboflavin on corneal substitute.
The tissue engineering scaffold was prepared by collagen and NHS/EDC (N-hydroxysuccinimide/1-ethyl-3-(3-dimethylaminopropyl)carbodiimide). The corneal button was irradiated with UVA of 370 nm for 30 minutes at a distance of 5 cm from the light source. Changes in the scaffold were detected by SDS-PAGE. Moreover, the substitute was exposed to pepsin, trypsin and collagenase solutions. The extent of corneal digestion was monitored daily. The scaffold without irradiation acted as control.
Irradiation with UVA/riboflavin allowed collagen α and β chains cross-linking into larger polymers. In addition, the digestion time was longer in the irradiated group than untreated controls in pepsin, trypsin and collagenase solutions.
These results suggest that photochemical collagen cross-linking may be a suitable method to improve mechanical properties and stability of the artificial cornea.