Understanding of the viscoelastic response of the human corneal stroma induced by riboflavin/UV-A cross-linking at the nano level

Cristina Labate, Maria Penelope De Santo, Giuseppe Lombardo, Marco Lombardo

Research output: Contribution to journalArticle


Purpose To investigate the viscoelastic changes of the human cornea induced by riboflavin/UV-A cross-linking using Atomic Force Microscopy (AFM) at the nano level. Methods Seven eye bank donor corneas were investigated, after gently removing the epithelium, using a commercial AFM in the force spectroscopy mode. Silicon cantilevers with tip radius of 10 nm and spring elastic constants between 26- and 86-N/m were used to probe the viscoelastic properties of the anterior stroma up to 3 μm indentation depth. Five specimens were tested before and after riboflavin/UV-A cross-linking; the other two specimens were chemically cross-linked using glutaraldehyde 2.5% solution and used as controls. The Young's modulus (E) and the hysteresis (H) of the corneal stroma were quantified as a function of the application load and scan rate. Results The Young' s modulus increased by a mean of 1.1-1.5 times after riboflavin/UV-A cross-linking (P

Original languageEnglish
Article numbere0122868
JournalPLoS One
Issue number4
Publication statusPublished - Apr 1 2015


ASJC Scopus subject areas

  • Agricultural and Biological Sciences(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Medicine(all)

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