Nanoemulsions Containing Incorporated Lipophilic Drug, Felodipine, and Microheterogeneous Adhesive Polymer Matrices Based on These Nanoemulsions

摘要

Oil-in-water nanoemulsions (NEs) have been obtained with a simple composition, in which a lipophilic non-micelle-forming nonionic surfactant (Tween 85) serves as both a dispersed phase and a stabilizer. The NEs remain in a metastable state for a long time (several months) and have a highly developed specific surface area (S-sp congruent to 63 m(2)/g) and a high solubilization capacity with respect to a lipophilic hypotensive drug, felodipine (FD). Nanosized droplets (d(av) congruent to 95 nm) of the NEs efficiently transport FD in an aqueous medium. The oil-in-water NEs of Tween 85 with incorporated FD and a solution of a polymer adhesive (a blend of polyisobutylenes having different molecular weights and polybutene) in heptane have been used to obtain oil(1)/water/oil(2) double emulsions, which are used as premixes for polymer microheterogeneous matrices. Obtained polymer films are characterized by a good adhesion to skin, the absence of FD crystallization, and a constant rate of its release for several hours.