Ricerc@Sapienza

In recent years, nanotechnology has allowed to formulate different ophthalmic vehicles in order to extend residence time in the eye after topical application, decreasing the number of instillations and improving patient¿s compliance. The goal of this study will be to develop an oil-in-water (O/W) nanoemulsions (NEs), composed of almond oil as the inner oil phase and Hepes or Palitzsch buffer as the outer aqueous phased, stabilized by non-ionic surfactants (Tween 20 or Tween 80). By modifying the oil/surfactant/water ratio, the best nanoemulsion formulations in terms of chemical-physical characteristics useful will be selected. In particular, hydrodynamic diameter, size distribution, ¿-potential, microviscosity and polarity of the internal oil phase, along with pH and osmolarity, stability in simulated tears and rheological properties will be evaluated. Furthermore, cytotoxicity studies using the Alamar Blue reduction assay in Y-79 (Human retinoblastoma cell line) cells will be performed to assure their compatibility for ocular administration. Finally, in order to stabilize the feasibility of formulated NEs for ocular delivery, in vitro both irritation studies and Draize test will be carried out.