title: [In vitro and in vivo evaluation of total flavones of Hippophae rhamnoides self-microemulsifying drug delivery system].
abstract: The goal of the study is to evaluate the self-microemulsifying drug delivery system (SMEDDS) which enhances the oral bioavailability of the poorly water-soluble drug, total flavones of Hippophae rhamnoides (TFH). It is orally administered for the protection of human cardiovascular system. Self-microemulsifying time, particle size, polydispersity index (PDI), morphological characterization, in vitro dispersity, stability, in situ intestinal absorption and relative bioavailability were investigated in detail. The TFH-SMEDDS rapidly formed fine oil-in-water microemulsions with 0.1 mol x L(-1) hydrochloride solution, with average size of which was less than 40 nm, PDI was below 0.2, and the particles of which were observed round-shaped under transmission electron microscope. Almost 90% of TFH (expressed with quercetin) was released from SMEDDS within 20 min, which was remarkably higher than that from common capsules. The stability test showed the TFH-SMEDDS maintained stable in 6 months under accelerated condition. In situ absorption study demonstrated the absorption rate constant of TFH-SMEDDS (expressed with quercetin) was significantly higher than that of TFH in ethanolic solution (P < 0.05). The absorption of TFH from SMEDDS showed a 4.18-fold increase in relative bioavailability (expressed with quercetin) compared with that of the suspension. The results suggest that SMEDDS is a promising drug delivery system to increase the oral bioavailability of TFH.
authors.affiliation: Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China.
authors.forename: Gui-ling
authors.initials: GL
authors.lastname: Li
authors.forename: Ya-ting
authors.initials: YT
authors.lastname: Fan
authors.forename: Yan-hui
authors.initials: YH
authors.lastname: Zhang
authors.forename: Yan-fang
authors.initials: YF
authors.lastname: Li
authors.forename: Xin-ru
authors.initials: XR
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Mei
authors.initials: M
authors.lastname: Li
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001682:Biological Availability; D004337:Drug Carriers; D016503:Drug Delivery Systems; D004655:Emulsions; D047309:Flavones / Q000008:administration & dosage / Q000302:isolation & purification / Q000493:pharmacokinetics*; D005638:Fruit / Q000737:chemistry; D031281:Hippophae / Q000737:chemistry*; D007408:Intestinal Absorption; D008297:Male; D010316:Particle Size; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D004337:Drug Carriers; D004655:Emulsions; D047309:Flavones