Lipid vesicles in the nano range with ionic and nonionic surfactants are known as transfersomes.  The presence of surfactant in the bilayer structure makes the vesicles very flexible in nature and helps them to permeate through the stratum corneum. The purpose of this research was to develop and characterize a transfersomal formulation of raloxifene HCl to deliver it into systemic circulation through the transdermal route. This was aimed to minimize the dose of the drug, thereby related adverse effects and to improve the bioavailability. The transfersomal formulation was prepared by the rotary evaporation method with phospholipon 90G and sorbitan 80. The particle size, zeta potential and polydispersity index (PDI) of the formulation were measured. The drug entrapment efficiency of the vesicles was determined by an indirect ultracentrifugation method. Ex-vivo skin permeation study, field emission scanning electron microscope (FESEM), transmission electron microscope (TEM) and confocal laser scanning microscopy (CLSM) study was performed as parts of advanced characterization of the developed formulation.  The size, charge, PDI and ex vivo transdermal flux (J) of the developed formulation showed favourable values required for the formulation stability. FESM and TEM study results ensured necessary attributes of the formulation for improved transdermal efficacy. CLSM study proved the distribution of the drug in the stratum corneum, viable epidermis and dermis with high fluorescence intensity. The developed nano transfersomes with raloxifene HCl showed encouraging results and can be further investigated for in vivo efficacy.

Keywords: Transfersome, raloxifene HCl, lipid vesicle, transdermal drug delivery.