PVA/anionic collagen membranes as drug carriers of ciprofloxacin hydrochloride with sustained antibacterial activity and potential use in the treatment of ulcerative keratitis.

Devices such as contact lenses and collagen shields have been used to improve the antibiotic bioavailability of eye drops formulations in the treatment of ulcerative keratitis. Nevertheless, these devices are not sustained drug delivery systems, and a combination with eye drops is necessary. In animal patients, it requires constant supervision by trained personnel to avoid device loss, which increases the cost of treatment. In this study, PVA/anionic collagen membranes containing ciprofloxacin or tobramycin were prepared using two different methodologies, and the release, physical and antimicrobial properties were evaluated. The membrane containing ciprofloxacin was selected as a sustained drug delivery system with antibacterial activity against Staphylococcus aureus and Escherichia coli during 48 h. Despite to be opaque, due to its heterogeneous morphology, this membrane had the adequate mechanical strength, water content, hydrophilicity, water vapor permeability, and surface pH to interact with cornea without causing discomfort. In the surface of this membrane it was observed dispersed collagen fibrils which could serve as a substrate for corneal proteinases, contributing to the reduction in stromal damage and enhancing the epithelium regeneration. These results encourage the idea these membranes are new cost-effective and safe alternatives to treat corneal ulcers in animal patients.