(175d) Investigation of the Interaction Between a Novel Drug Delivery System and an Epithelial Cell Layer

Surgery and other invasive processes are the current treatment options for patients with diabetic retinopathy, glaucoma, and age-related macular degeneration, which are eye diseases that affect at least nine million Americans. We are developing a targeted drug-delivery system, which would provide a non-invasive option for treatment. The system features a collagen membrane with drug-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles incorporated into a thin membrane. This membrane can be worn by a patient in conjunction with a contact lens, and provides for continuous drug release. The purpose of this project is to study the interactions of lidocaine-loaded nanoparticles in a collagen membrane with a layer of corneal epithelial cells. Lidocaine-loaded PLGA nanoparticles were made and characterized by measuring size and drug content. Nanoparticles were mixed into a collagen solution and then gelled to form a thin membrane. Corneal epithelial cells were cultured on semipermeable well inserts to form a confluent layer of cells. The cell layer was exposed to the collagen membrane containing the lidocaine-loaded nanoparticles. Measurements were taken to determine cell viability and permeability, as well as the amount of lidocaine that crosses the cell layer. Results showed that lidocaine was released from the system and delivered across the cell layer. The release profile shows an initial burst release, followed by steady drug release over the testing period. Cell viability decreased with the application of the membranes, compared to a control sample of cells only. Further work is being done to determine the cause of cell death and to test the system for longer periods of time