Enhanced oromucosal delivery of progesterone via hexosomes

Purpose. Formulation and characterization of progesterone loaded hexosomes employing a novel method for oromucosal delivery. Method. Hexosomes were prepared employing a method in which ethanolic solution of lipid phase (monolein and oleic acid) was vortexed with aqueous phase (surfactant solution) and characterized for particle size, morphology and internal structure. FT-IR and confocal laser scanning microscopy (CLSM) were performed to investigate the possible mechanism and penetration pathway of hexosomes within the mucosa. Results. Hexosomes exhibited anisotropy, hexagonal shape and nanometric size (251.2 +/- 1.8 nm). Internal structure confirmed by X-ray diffraction peaks with spacing ratio of root 1:root 3:root 4 proved two-dimensional hexagonal arrangements. Entrapment efficiency of system was greater than 95%. In vitro release studies revealed an enhanced transmucosal flux (4.67 +/- 0.14 mu g cm(-2) h(-1)) and decreased lag time (1.54 h) across albino rabbit mucosa. FT-IR and CLSM of treated mucosa shows lipid extraction phenomena as well as structural irregularities within intercellular lipids respectively. These irregularities can function as 'virtual channels' facilitating hexosome's penetration. Conclusion. Developed hexosomes formulation exhibited high entrapment efficiency, high permeability and better stability on storage, thus proposing itself a novel carrier for enhanced oromucosal delivery of progesterone.