title: [TLC analysis of harpagoside in devil claw extract and its tablets].
abstract: OBJECTIVE
  To set up a method for TLC identification of the Devil Claw Extract and its tablets, and make a quantitative analysis of harpagoside the main active constituent in the Extract.
  
  
  METHODS
  A characteristic TLC chromatogram was obtained by using pre-coated silica gel 60F254 plate, chloroform-ethyl acetate-methanol-water as the solvent system and 5% vanillin-sulfuric acid solution or 10% sulfuric acid-ethanol solution as the spray reagent; and quantitative analysis was carried out using silica gel plate modified by 1% sodium hydroxide, and UV absorptive scanning at 283 nm.
  
  
  RESULTS
  The regression equation is Y = 20.33X + 92.72, r = 0.9993, linear range between 16.8-151.2 ng, and average recovery 101.2%.
  
  
  CONCLUSIONS
  This method has been validated by linearity, stability, sensitivity and reproducibility tests, and proved to be accordant with the requirement for quantitative analysis of the herbal medicine in question.
authors.affiliation: Guangzhou Municipal Institute for Drug Control, Guangzhou 510160.
authors.forename: H
authors.initials: H
authors.lastname: Qian
authors.forename: P
authors.initials: P
authors.lastname: Xie
mesh_terms: D002855:Chromatography, Thin Layer; D006027:Glycosides / Q000032:analysis*; D031684:Harpagophytum / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D011714:Pyrans / Q000032:analysis*; D011786:Quality Control; D013607:Tablets
chemical_list: D006027:Glycosides; D010936:Plant Extracts; D011714:Pyrans; D013607:Tablets; C033249:harpagoside