Effect of operational conditions on the supercritical carbon dioxide impregnation of anti-inflammatory and antibiotic drugs in rigid commercial intraocular lenses
Résumé
Drug/lense combinations have proven significant in the field of ocular therapeutics. The development of innovative systems and elaboration processes is an upcoming issue for ocular drug delivery. One challenging issue is the elaboration of drug loaded intraocular lenses (IOLs) to combine cataract surgery and post-operative treatments in a single procedure. In this work, we are studying the elaboration of such systems while using a green process using supercritical fluids for impregnating ophthalmic drugs on commercial IOLs. More particularly, rigid commercial intraocular lenses made from Poly (Methyl MethAcrylate) (PMMA), used in cataract surgery, are loaded with dexamethasone 21- phosphate disodium salt (DXP, an anti-inflammatory drug) and ciprofloxacin (CIP, an antibiotic) in order to prevent short- and mid-term postoperative complications.
Supercritical impregnations were carried out in a batch mode and impregnation yields were determined through drug release kinetic studies in a solution simulating the aqueous humor. Before performing an experimental design, preliminary impregnation assays were conducted in order to delimit the operating domain. Transparent IOLs presenting an effective impregnation were obtained. The highest impregnation yields for DXP and CIP in PMMA IOLs were 18.3 and 2.8 μgdrug/mgIOL respectively. Despite the low solubility of each drug in the fluid phase, homogeneous and in-depth impregnations were successfully obtained with a prolonged drug delivery (about 40 days) for most impregnation experiments.