title: Study on the optical property and biocompatibility of a tissue engineering cornea.
abstract: OBJECTIVE
  To study the optical property and biocompatibility of a tissue engineering cornea.
  
  
  METHODS
  : The cross-linker of N-(3-Dimethylaminoropyl)-N'ethylcarbodiimide hydrochloride (EDC)/N-Hydroxysuccinimide (NHS) was mixed with Type I collagen at 10% (weight/volume). The final solution was molded to the shape of a corneal contact lens. The collagen concentrations of 10%, 12.5%, 15%, 17.5% and 20% artificial corneas were tested by UV/vis-spectroscopy for their transparency compared with normal rat cornea. 10-0 sutures were knotted on the edges of substitute to measure the corneal buttons's mechanical properties. Normal rat corneal tissue primary culture on the collagen scaffold was observed in 4 weeks. Histopathologic examinations were performed after 4 weeks of in vitro culturing.
  
  
  RESULTS
  The collagen scaffold appearance was similar to that of soft contact lens. With the increase of collagen concentration, the transparency of artificial corneal buttons was diminished, but the toughness of the scaffold was enhanced. The scaffold transparency in the 10% concentration collagen group resembled normal rat cornea. To knot and embed the scaffold under the microscope, 20% concentration collagen group was more effective during implantation than lower concentrations of collagen group. In the first 3 weeks, corneal cell proliferation was highly active. The shapes of cells that grew on the substitute had no significant difference when compared with the cells before they were moved to the scaffold. However, on the fortieth day, most cells detached from the scaffold and died. Histopathologic examination of the primary culture scaffold revealed well grown corneal cells tightly attached to the scaffold in the former culturing.
  
  
  CONCLUSIONS
  Collagen scaffold can be molded to the shape of soft contact corneal lens with NHS/EDC. The biological stability and biocompatibility of collagen from animal species may be used as material in preparing to engineer artificial corneal scaffold.
authors.affiliation: Department of Ophthalmology, the Fourth Affiliated Hospital of China Medical University, Eye Hospital of China Medical University, Provincial Key Laboratory of Lens Research, Shenyang 110005, Liaoning Province, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Nakahara
authors.forename: Dwight
authors.initials: D
authors.lastname: Xuan
authors.forename: Di
authors.initials: D
authors.lastname: Wu
authors.forename: Fang-Kun
authors.initials: FK
authors.lastname: Zhao
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Li
authors.forename: Jin-Song
authors.initials: JS
authors.lastname: Zhang