Huizhen Wang1,2, Yuqing Cui1, Qingxue Fu3, Bing Deng1, Guowen Li4, Jun Yang2, Tao Wu3, Yan Xie1. 1. a Research Center for Health and Nutrition , Shanghai University of Traditional Chinese Medicine , Shanghai , China . 2. b Department of Pharmacy , Xiangshan Hospital of Traditional Chinese Medicine , Shanghai , China . 3. c Institute of Chinese Materia Medica , Shanghai University of Traditional Chinese Medicine , Shanghai , China , and. 4. d Department of Pharmacy , Shanghai TCM-integrated Hospital , Shanghai , China.
Abstract
AIM: A phospholipid complex (TFH-PC) was prepared to increase the oral bioavailability of isorhamnetin, kaempferol, and quercetin from TFH (total flavones of Hippophae rhamnoides L.). METHODS: Solvent evaporation was used to prepare TFH-PC. Relevant parameters were investigated based on the complexation rate of isorhamnetin, kaempferol, and quercetin. Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), X-ray power diffraction (X-RPD), and scanning electron microscopy (SEM) were used for characterization. Solubility, octanol-water partition coefficient (log P), dissolution rate, and in vivo pharmacokinetics were also investigated. RESULTS: TFH-PC was successfully prepared in tetrahydrofuran with a drug to phospholipid ratio of 1:1, reaction temperature of 20 °C, and a reaction time of 1 h. The complexation rates of isorhamnetin, kaempferol, and quercetin were 97.7%, 95.97%, and 92.23%, respectively. FT-IR, DSC, X-RPD, and SEM confirmed the formation of TFH-PC. The aqueous solubilities of the three flavonoids in TFH-PC increased 22.0-26.8-fold compared with TFH. The dissolution of isorhamnetin, kaempferol, and quercetin in TFH-PC was 84.32%, 90.77%, and 100% within 10 min, respectively, greatly improved over TFH. After oral administration of TFH-PC in rats, the bioavailability of isorhamnetin, kaempferol, and quercetin in TFH-PC relative to TFH was 223%, 172%, and 242%, respectively. CONCLUSION: The oral absorption of isorhamnetin, kaempferol, and quercetin was significantly improved in TFH-PC, mainly due to increased solubility and dissolution rate. This phospholipid complex shows potential for oral delivery of the flavonoids in TFH.
AIM: A phospholipid complex (TFH-PC) was prepared to increase the oral bioavailability of isorhamnetin, kaempferol, and quercetin from TFH (total flavones of Hippophae rhamnoides L.). METHODS: Solvent evaporation was used to prepare TFH-PC. Relevant parameters were investigated based on the complexation rate of isorhamnetin, kaempferol, and quercetin. Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), X-ray power diffraction (X-RPD), and scanning electron microscopy (SEM) were used for characterization. Solubility, octanol-water partition coefficient (log P), dissolution rate, and in vivo pharmacokinetics were also investigated. RESULTS:TFH-PC was successfully prepared in tetrahydrofuran with a drug to phospholipid ratio of 1:1, reaction temperature of 20 °C, and a reaction time of 1 h. The complexation rates of isorhamnetin, kaempferol, and quercetin were 97.7%, 95.97%, and 92.23%, respectively. FT-IR, DSC, X-RPD, and SEM confirmed the formation of TFH-PC. The aqueous solubilities of the three flavonoids in TFH-PC increased 22.0-26.8-fold compared with TFH. The dissolution of isorhamnetin, kaempferol, and quercetin in TFH-PC was 84.32%, 90.77%, and 100% within 10 min, respectively, greatly improved over TFH. After oral administration of TFH-PC in rats, the bioavailability of isorhamnetin, kaempferol, and quercetin in TFH-PC relative to TFH was 223%, 172%, and 242%, respectively. CONCLUSION: The oral absorption of isorhamnetin, kaempferol, and quercetin was significantly improved in TFH-PC, mainly due to increased solubility and dissolution rate. This phospholipid complex shows potential for oral delivery of the flavonoids in TFH.