title: [Preparation of silybin-phospholipid complex and its bioavailability in rats].
abstract: OBJECTIVE
  To prepare silybin-phospholipid complex and study its physicochemical properties. To compare the pharmacokinetic characteristics and bioavailability after oral administration of silybinphospholipid complex and silybin material in rats.
  
  
  METHODS
  Using acetone as a reaction medium, silybin and phospholipid were resolved into the medium, when the organic solvent was clear, then removed under vacuum evaporation, silybin-phospholipid complex was obtained. The new complex' s physicochemical properties including DSC, UV, IR were determined. The concentrations of non-conjugated and total silybin after oral administration of silybin-phospholipid complex and silybin material at different time in rats were determined by RP-HPLC. The pharmacokinetic parameters were computed by software program 3P97.
  
  
  RESULTS
  Experiment results showed that silybin and phospholipid in the silybin-phospholipid complex were combined by non-covalent-bond, not forming a new compound and the solubility of silybin-phospholipid complex in water and n-octanol was effectively enhanced. It was found that mean plasma concentration-time curve of silybin after oral administration of silybin-phospholipid complex in rats was in accordance with one-compartment model with first-order absorption. Pharmacokinetic parameters of non-conjugated and total silybin in rats were respectively T(max) 10 min and 2 h; C(max) 0.11 and 1.08 microg x mL(-1); T1/2 2.18 and 3.84 h; AUC(0-infinity) 1.71 and 12.94 microg x mL(-1) x h. However, after oral administration of silybin material, plasma levels of both non-conjugated and total silybin were within the analytical detection limit.
  
  
  CONCLUSIONS
  It was concluded that after oral administration of silybin-phospholipid complex in rats the bioavailability of silybin increased greatly. This was mainly due to an obvious improvement of the lipophilic property of silybin-phospholipid complex compared with silybin material and an increase in gastrointestinal absorption.
authors.affiliation: Department of Pharmaceutics, China Pharmaceutical University, Nanjing 210009, China.
authors.forename: Yan-Yu
authors.initials: YY
authors.lastname: Xiao
authors.forename: Yun-Mei
authors.initials: YM
authors.lastname: Song
authors.forename: Zhi-Peng
authors.initials: ZP
authors.lastname: Chen
authors.forename: Qi-Neng
authors.initials: QN
authors.lastname: Ping
mesh_terms: D000284:Administration, Oral; D000818:Animals; D019540:Area Under Curve; D001682:Biological Availability; D004339:Drug Compounding; D008297:Male; D010743:Phospholipids / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D000077385:Silybin; D012838:Silymarin / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics; D012995:Solubility
chemical_list: D010743:Phospholipids; D012838:Silymarin; D000077385:Silybin