title: Transparency in a fibrin and fibrin-agarose corneal stroma substitute generated by tissue engineering.
abstract: OBJECTIVE
  To examine the transparency characteristics at different times of development in the culture of 2 different types of human corneal stroma substitutes generated by tissue engineering using human fibrin or human fibrin and 0.1% agarose, with human keratocytes entrapped within.
  
  
  METHODS
  The transparency of these artificial corneal stromas was analyzed after 1, 7, 14, 21, and 28 days of development in culture by determining the scattering and absorption coefficients from the spectral reflectance data of each sample using the Kubelka-Munk equations.
  
  
  RESULTS
  The scattering coefficient of both types of bioengineered tissues tended to increase with culture time and wavelength until 550 nm, whereby a slight decrease was observed for longer wavelengths. In general, the spectral distribution of the Kubelka-Munk scattering coefficient of the fibrin-agarose corneal constructs was more stable than that of the fibrin constructs. The absorption coefficient of the human fibrin and fibrin-agarose corneal substitutes tended to decrease with increasing wavelength, and their absolute values were higher for fibrin-agarose than for fibrin scaffolds, especially for short wavelengths. In addition, the spectral transmittance behavior of both types of tissue analyzed was similar to the ones of the theoretical and control corneas, with absolute values above 90% for all wavelengths at 28 days of development.
  
  
  CONCLUSIONS
  The transparency, scattering, and absorption of both fibrin and fibrin-agarose corneal stroma substitutes indicate that these new biomaterials could be adequate for clinical use.
authors.affiliation: Department of Optics, Faculty of Sciences, University of Granada, Granada, Spain.
authors.forename: Juan de la Cruz
authors.initials: Jde L
authors.lastname: Cardona
authors.forename: Ana-Maria
authors.initials: AM
authors.lastname: Ionescu
authors.forename: Ricardo
authors.initials: R
authors.lastname: Gómez-Sotomayor
authors.forename: Miguel
authors.initials: M
authors.lastname: González-Andrades
authors.forename: Antonio
authors.initials: A
authors.lastname: Campos
authors.forename: Miguel
authors.initials: M
authors.lastname: Alaminos
authors.forename: María del Mar
authors.initials: Mdel M
authors.lastname: Pérez
mesh_terms: D001187:Artificial Organs; D060527:Corneal Keratocytes / Q000166:cytology*; D003319:Corneal Stroma / Q000166:cytology / Q000502:physiology*; D005337:Fibrin; D006801:Humans; D008027:Light; D012542:Scattering, Radiation; D012685:Sepharose; D013053:Spectrophotometry; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry
chemical_list: D005337:Fibrin; D012685:Sepharose