title: Investigation of a nanoemulsion as vehicle for transdermal delivery of amlodipine.
abstract: A novel oil-in-water nanoemulsion system for transdermal delivery of amlodipine was studied. Pseudoternary phase diagrams were developed and various nanoemulsion formulations were prepared using oleic acid (oil phase), Tween 20 (surfactant) and Transcutol P (co-surfactant). The effects of content of oleic acid and surfactant/co-surfactant ratio (S(mix)) on skin permeation of amlodipine were evaluated through excised rat skin using a Franz diffusion cell. Highest permeation rate and permeability coefficient was found at low oil and S(mix) concentration. On increasing the same, fluxes were further decreased, probably due to increased globule size and decreased thermodynamic activity of drug at higher surfactant mixture concentration. The optimum nanoemulsion formulation consisted of 2% oil (oleic acid), 20% surfactant (Tween 20), 10% co-surfactant (S(mix) 2 : 1) and water exhibited highest skin permeation rate of 49.681 +/- 1.98 microg/cm/h and permeability coefficient of 0.497 +/- 0.056 cm2/h. The optimized nanoemulsion was characterized for globules size, morphology, viscosity, and pH. The result suggests that nanoemulsions are potential vehicles for improved transdermal delivery of amlodipine.
authors.affiliation: Department of Pharmaceutics, Faculty of Pharmacy, Hamdard University, New Delhi, India.
authors.forename: D
authors.initials: D
authors.lastname: Kumar
authors.forename: M
authors.initials: M
authors.lastname: Aqil
authors.forename: M
authors.initials: M
authors.lastname: Rizwan
authors.forename: Y
authors.initials: Y
authors.lastname: Sultana
authors.forename: M
authors.initials: M
authors.lastname: Ali