EP0696452A1 — Nanoemulsion of the oil in water type, useful as an ophthalmic vehicle and process for the preparation thereof

USPTO Abstract

The nanoemulsion comprises: 0.1-10% (w/v) of an oil; 0.1-10% (w/v) of a non-ionic surface active agent; a maximum of 0.01% (w/v) of benzalkonium chloride; a drug or a precursor or active substance; and optionally, one or several of the following components: an isotonizing agent, a viscosity modifying agent or stabilizer, a buffer and/or an antioxidant in variable proportions. The process comprises: (a) preparing an aqueous phase containing, among others, a non-ionic surface active agent; (b) preparing an organic phase containing dissolved an oil and an active substance in an organic water miscible solvent in all proportions; (c) including the organic phase to the aqueous phase under moderate agitation; and (d) totally evaporating the organic solvent and part of the water up to the final desired volume. Important applications as an ophthalmic vehicle in preparations used to treat eye disorders and diseases.