title: [Simultaneous determination of four components in Hedyotis diffusa oral solution by reversed-phase HPLC].
abstract: OBJECTIVE
  A new method for simultaneous determination of four methyl-3, 4-dihydroxybenzoate ( I ), P-coumaric acid (II), ferulaic acid (III) and E-6-O-P-coumaroyl scandoside methyl ester (IV) in Hedyotis diffusa oral solution by reversed-phase HPLC was developed.
  
  
  METHODS
  The separation was performed on a Diamonsil C18 column (4.6 mm x 250 mm, 5 microm) with gradient elution. A-acetonitrile, B-methonal-water-glacial acetic acid (5: 95: 0.25), 0-20 min, 1% -16% A; 2042 min, 16% A; 42-46 min, 16%-20%A; 46-65 min, 20% A. The UV detection was set at 265 nm; flow rate 1.0 mL x min(-1).
  
  
  RESULTS
  There was good linearity between the peak area and concentration at the ranges of 2.1-105 (r = 0.999 8), 3.5-175 (r = 0.999 8), 1.72-86 (r = 0.999 9), 4.0-200 mg x L(-1) (r = 1.000 0) for I, II, III and IV respectively. The average recoveries of I, II, III and IV were 99.9%, 97.9%, 98.6% and 98.1%.
  
  
  CONCLUSIONS
  The method is rapid, simple and accurate, and it can be used for the evaluation of H. diffusa oral solution.
authors.affiliation: School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China.
authors.forename: Hong-Fei
authors.initials: HF
authors.lastname: Zhang
authors.forename: Hua-Yan
authors.initials: HY
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Xing-Jie
authors.initials: XJ
authors.lastname: Guo
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004365:Drugs, Chinese Herbal / Q000737:chemistry*; D032064:Hedyotis / Q000737:chemistry*; D015203:Reproducibility of Results
chemical_list: D004365:Drugs, Chinese Herbal