title: [Determination of equilibrium solubility and n-octanol/water partition coefficient of pulchinenosiden D by HPLC].
abstract: OBJECTIVE
  To determine the equilibrium solubility of pulchinenosiden D in different solvents and its n-octanol/water partition coefficients.
  
  
  METHODS
  Combining shaking flask method and high performance liquid chromatography (HPLC) to detect the n-octanol/water partition coefficients of pulchinenosiden D, the equilibrium solubility of pulchinenosiden D in six organic solvents and different pH buffer solution were determined by HPLC analysis.
  
  
  RESULTS
  n-Octanol/water partition coefficients of pulchinenosiden D in different pH were greater than zero, the equilibrium solubility of pulchinenosiden D was increased with increase the pH of the buffer solution. The maximum equilibrium solubility of pulchinenosiden D was 255.89 g x L(-1) in methanol, and minimum equilibrium solubility of pulchinenosiden D was 0.20 g x L(-1) in acetonitrile.
  
  
  CONCLUSIONS
  Under gastrointestinal physiological conditions, pulchinenosiden D exists in molecular state and it has good absorption but poor water-solubility, so increasing the dissolution rate of pulchinenosiden D may enhance its bioavailability.
authors.forename: Xiao-Yong
authors.initials: XY
authors.lastname: Rao
authors.forename: Shan
authors.initials: S
authors.lastname: Yin
authors.forename: Guo-Song
authors.initials: GS
authors.lastname: Zhang
authors.forename: Xiao-Jian
authors.initials: XJ
authors.lastname: Luo
authors.forename: Hui
authors.initials: H
authors.lastname: Jian
authors.forename: Yu-Lin
authors.initials: YL
authors.lastname: Feng
authors.forename: Shi-Lin
authors.initials: SL
authors.lastname: Yang
mesh_terms: D020003:1-Octanol / Q000737:chemistry*; D000097:Acetonitriles / Q000737:chemistry; D001682:Biological Availability; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004365:Drugs, Chinese Herbal / Q000737:chemistry* / Q000493:pharmacokinetics; D041981:Gastrointestinal Tract / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007408:Intestinal Absorption; D007700:Kinetics; D000432:Methanol / Q000737:chemistry; D031946:Pulsatilla / Q000737:chemistry; D012995:Solubility; D012997:Solvents / Q000737:chemistry; D014867:Water / Q000737:chemistry*
chemical_list: D000097:Acetonitriles; D004365:Drugs, Chinese Herbal; D012997:Solvents; D014867:Water; D020003:1-Octanol; D000432:Methanol; C032159:acetonitrile