LAUSR

BACKGROUND Amphotericin B (AMB) is water-insoluble polyene, which has a broad spectrum of antifungal activity. The hydrophobic drug only exits in the phospholipid bilayer, leading to a low-drug liposomal loading capacity. OBJECTIVES This study is designed to prepare water-soluble inclusion complex (IC) between AMB and cyclodextrin (CD) to formulate liposomal vesicles, double-loaded with drug molecules in the phospholipid bilayer and AMB/CD IC in the aqueous core. METHODS Water-soluble AMB/CD IC was prepared by pH adjustment of the aqueous media and consequently characterized by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). Liposomes double-loaded with AMB were formulated by the thin-film hydration method and accordingly evaluated for vesicle size, polydispersity index, entrapment efficiency, zeta potential and in vitro drug leakage. RESULTS Hydroxypropyl β cyclodextrin (HP-β-CD) better solubilized AMB than both α-CD and β-CD e.g, the concentration of water-soluble AMB/HP-β-CD IC could reach 465 µg/mL. Both DSC and SEM data illustrated that the drug no longer existed in its crystalline form, a in AMB/HP-β-CD IC. Liposomes double-loaded with hydrophilic AMB/HP-β-CD IC and hydrophobic AMB had a diameter of 270 nm, polydispersity index less than 0.27 and zeta potential ca. - 42.8 mV. Moreover, liposomes double loaded with AMB enhanced drug-liposomal loading capacity by 25%, less leaked drug in phosphate buffer pH 7.4 at 37oC in comparison to liposomes loaded with only hydrophobic AMB. CONCLUSION Liposomes double loaded with AMB and AMB/HP-β-CD IC increased drug-encapsulation ability and in vitro stability, suggesting potential drug delivery systems.