title: Preparation and evaluation of self-microemulsifying drug delivery system of baicalein.
abstract: The main object of this work is to prepare self-microemulsifying drug delivery system (SMEDDS) for oral bioavailability enhancement of a poorly water-soluble drug, baicalein. SMEDDS is the mixture of surfactants, cosurfactants, and oils, which are emulsified in aqueous media under conditions of gentle agitation or gastrointestinal motility. Solubility of baicalein was determined in various vehicles. Pseudo-ternary phase diagrams were constructed to identify the efficient self-emulsification region and droplet size distributions of the resultant microemulsions were determined using a particle size analyzer. Optimized SMEDDS formulations for baicalein were Cremophor RH40 (53.57%) as surfactant, Transcutol P (21.43%) as cosurfactant, and Caprylic capric triglyceride (ODO, 25%) as oil. The drug release rate of SMEDDS was significantly higher than that of the baicalein suspension. Comparison of the pharmacokinetics between baicalein-loaded SMEDDS and baicalein suspension was also performed in rats. The plasma concentrations of baicalein and baicalin, its mainly conjugated metabolite, were determined by HPLC method. The in vivo results showed that the absorption of baicalein from SMEDDS resulted in about 200.7% increase in relative bioavailability compared with that of the baicalein suspension. Our studies illustrated the potential use of SMEDDS for the delivery of hydrophobic compounds, such as baicalein by the oral route.
authors.affiliation: School of Pharmacy, Chongqing Medical University, Chongqing 400016, China.
authors.forename: Wenli
authors.initials: W
authors.lastname: Liu
authors.forename: Rui
authors.initials: R
authors.lastname: Tian
authors.forename: Wenjing
authors.initials: W
authors.lastname: Hu
authors.forename: Yuntao
authors.initials: Y
authors.lastname: Jia
authors.forename: Huiming
authors.initials: H
authors.lastname: Jiang
authors.forename: Jingqing
authors.initials: J
authors.lastname: Zhang
authors.forename: Liangke
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000284:Administration, Oral; D000818:Animals; D019540:Area Under Curve; D001682:Biological Availability; D004304:Dosage Forms; D004655:Emulsions / Q000737:chemistry; D004791:Enzyme Inhibitors / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*; D044950:Flavanones / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*; D008297:Male; D015394:Molecular Structure; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D004304:Dosage Forms; D004655:Emulsions; D004791:Enzyme Inhibitors; D044950:Flavanones; C006680:baicalein