Photograph of corneal buttons of rabbit eyes soaked with riboflavin-5-phosphate nanoemulsion or standard 0.1% riboflavin.

<p>Cornea with intact epithelium after exposure to 0.5% riboflavin-5-phosphate nanoemulsion for 240 minutes (A). Cornea with intact epithelium after exposure to the standard 0.1% riboflavin solution for 240 minutes (B). De-epithelialized cornea exposed to 0.1% riboflavin solution for 30 minutes - standard technique (C).</p

Stability evaluation of the nanoemulsions over time.

<p>Key: (□) Unloaded nanoemulsion (R = 0.9965); (○) Riboflavin-5-loaded nanoemulsion (R = 0.9927). Mean of 10 analytical determinations ± standart deviation.</p

Change of transmittance and absorption coefficient of rabbit corneas in the course of time.

<p>Transmittance change (A) and absorption coefficient change (B) of corneas soaked with riboflavin formulations. Dashed lines show group I values (standard treatment).</p

Absorption spectra of riboflavin-5-phosphate nanoemulsion and riboflavin-base nanoemulsion.

<p>Absorption spectra of riboflavin-5-phosphate nanoemulsion and riboflavin-base nanoemulsion.</p

Photograph of the corneal buttons of rabbit eyes of after exposure to different riboflavins.

<p>Corneas with intact epithelium (A, B, and C) after exposure to 0.1% riboflavin-dextran solution for 30 minutes (A) and for 240 minutes (B), as well as after exposure to concentrated 1% riboflavin-dextran for 240 minutes (C). De-epithelialized cornea soaked with 0.1% riboflavin-dextran for 30 minutes - standard technique (D). The yellow staining shows that riboflavin diffused into the stroma only when the epithelium was removed.</p