Solid dispersions of artemether and polyethylene glycol 6000 (PEG6000) were prepared in ratio 12 : 88 (group-1). Self-emulsified\nsolid dispersions of artemether were prepared by using polyethylene glycol 6000, Cremophor-A25, olive oil, Transcutol, and\nhydroxypropyl methylcellulose (HPMC) in ratio 12 : 75 : 5 : 4 : 2 : 2, respectively (group-2). In third group, only Cremophor-\nA25 was replaced with Poloxamer 188 compared to group-2. The solid dispersions and self-emulsified solid dispersions were\nprepared by physical and freeze dried methods, respectively. All samples were characterized by X-ray diffraction, attenuated total\nreflectance Fourier transforminfrared spectroscopy, differential scanning calorimeter, scanning electron microscopy, and solubility,\ndissolution, and stability studies. X-ray diffraction pattern revealed artemether complete crystalline, whereas physical mixture\nand freeze-dried mixture of all three groups showed reduced peak intensities. In attenuated total reflectance Fourier transform\ninfrared spectroscopy spectra, Cââ?¬â??H stretching vibrations of artemether were masked in all prepared samples, while Cââ?¬â??H stretching\nvibrations were representative of polyethylene glycol 6000, Cremophor-A25, and Poloxamer 188. Differential scanning calorimetry\nshowed decreased melting endotherm and increased enthalpy change (?????) in both physical mixture and freeze-dried mixtures\nof all groups. Scanning electron microscopy of freeze-dried mixtures of all samples showed glassy appearance, size reduction, and\nembedment, while their physical mixture showed size reduction and embedment of artemether by excipients. In group-1, solubility\nwas improved up to 15 times, whereas group-2 showed up to 121 times increase but, in group-3, when Poloxamer 188 was used\ninstead of Cremophor-A25, solubility of freeze-dried mixtures was increased up to 135 times. In fasted state simulated gastric fluid\nat pH 1.6, the dissolution of physical mixture was increased up to 12 times and freeze-dried mixtures up to 15 times. The stability of\nartemether was substantially enhanced in freeze-dried mixtures by using polyethylene glycol 6000, Cremophor-A25, and Poloxamer\n188 of self-emulsified solid dispersions of artemether in Hankââ?¬â?¢s balanced salt solution at pH 7.4.
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