Abstract
Purpose :
Contact lenses have been explored as a drug delivery method to improve drug contact time and bioavailability in the eye. However no current studies exist outlining the diffusion patters of medications through them. We sought to describe the migration of ciprofloxacin, prednisolone acetate and phosphate through soft contact lenses via an experimental model utilizing Franz cells.
Methods :
FDA class 1-4 soft contact lenses were placed on top on the receiving chamber of Franz cells. With the cap in place, a 500 microliter drop was placed on the lens. The jacket of the cells were warmed to 37 degrees. Sink conditions were maintained in the pH neutral receiving chamber via a small stir bar. Samples from the receiving chamber vehicle were collected at various times and analyzed with UV/Vis spectroscopy. The resulting absorptions were plotted vs a Beer’s Law plot to determine the concentration of drug diffused through the contact lens. M1 and M3 were analyzed to calculate the time and amount of drug which diffused through the lens.
Results :
Utilizing a curve fit model analyzed by ANOVA testing, ciprofloxacin is the only drug tested that shows no statistically significant difference in diffusion characteristics between the 4 different classes of contact lenses. Ciprofloxacin did diffuse significantly faster than either of the prednisolone salts. It is also of note, the prednisolone acetate migrated significantly slower than the phosphate salt. In every case, the drug diffused in a reproducible manner, allowing for predictable kinetics of drug release.
Conclusions :
Our data demonstrates the possibility for contact lenses to absorb and slowly release drug in a predictable and rate controlled manner. The drug solubility characteristics and water content of the lens appear to affect medication migration rates. More research is needed to further understand the characteristics of the interactions between lens and drug.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.