2. Universidad Cardenal Herrera-CEU

The objective of this research was to develop and evaluate an ocular insert for the controlled drug delivery of moxifloxacin which could perhaps be used in the treatment of corneal keratitis or even bacterial endophthalmitis. We have evaluated the ex vivo ocular diffusion of moxifloxacin through rabbit cornea, both fresh and preserved under different conditions. Histological studies were also carried out. Subsequently, drug matrix inserts were prepared using bioadhesive polymers. The inserts were evaluated for their physicochemical parameters. Ophthalmic ex vivo permeation of moxifloxacin was carried out with the most promising insert. The formulate insert was thin and provided higher ocular diffusion than commercial formulations. Ocular diffusion studies revealed significant differences between fresh and frozen corneas. Histological examinations also showed differences in the thickness of stroma between fresh and frozen corneas. The ophthalmic insert we have developed allows a larger quantity of moxifloxacin to permeate through the cornea than existing commercial formulations of the drug. Ocular delivery of moxifloxacin with this insert could be a new approach for the treatment of eye diseases.

Percutaneous transdermal absorption of esculetin (6,7-dihydroxycoumarin), an oxidative damage inhibitor, was evaluated by means of in vitro permeation studies in which vertical Franz-type diffusion cells and pig ear skin were employed. To determine the absorption of esculetin, we validated a simple, accurate, precise, and rapid HPLC-UV method. Additionally, the effects of several percutaneous enhancers were studied. Pretreatment of porcine skin was performed with ethanol (control vehicle), decenoic acid, oleic acid, R-(+)-limonene, and laurocapram (Azone®) (5% in ethanol, w/w, respectively). Pretreatment of skin with oleic acid or laurocapram led to statistically significant differences in the transdermal flux of esculetin with respect to controls. Of the two enhancers, laurocapram showed the greatest capacity to enhance the flux of esculetin across pig skin.