title: Quantitative analysis of major dibenzocyclooctane lignans in Schisandrae fructus by online TLC-DART-MS.
abstract: BACKGROUND
  Direct analysis in real time (DART) ion source is a powerful ionising technique for the quick and easy detection of various organic molecules without any sample preparation steps, but the lack of quantitation capacity limits its extensive use in the field of phytochemical analysis.
  
  
  OBJECTIVE
  To improvise a new system which utilize DART-MS as a hyphenated detector for quantitation.
  
  
  METHODS
  A total extract of Schisandra chinensis fruit was analyzed on a TLC plate and three major lignan compounds were quantitated by three different methods of UV densitometry, TLC-DART-MS and HPLC-UV to compare the efficiency of each method. To introduce the TLC plate into the DART ion source at a constant velocity, a syringe pump was employed. The DART-MS total ion current chromatogram was recorded for the entire TLC plate. The concentration of each lignan compound was calculated from the calibration curve established with standard compound.
  
  
  RESULTS
  Gomisin A, gomisin N and schisandrin were well separated on a silica-coated TLC plate and the specific ion current chromatograms were successfully acquired from the TLC-DART-MS system. The TLC-DART-MS system for the quantitation of natural products showed better linearity and specificity than TLC densitometry, and consumed less time and solvent than conventional HPLC method.
  
  
  CONCLUSIONS
  A hyphenated system for the quantitation of phytochemicals from crude herbal drugs was successfully established. This system was shown to have a powerful analytical capacity for the prompt and efficient quantitation of natural products from crude drugs.
authors.affiliation: Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Seoul 130-701, Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Myung Sook
authors.initials: MS
authors.lastname: Oh
authors.forename: Jongki
authors.initials: J
authors.lastname: Hong
authors.forename: Young Pyo
authors.initials: YP
authors.lastname: Jang
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002855:Chromatography, Thin Layer / Q000379:methods*; D034242:Cyclooctanes / Q000032:analysis* / Q000737:chemistry; D003720:Densitometry / Q000379:methods; D004149:Dioxoles / Q000032:analysis / Q000737:chemistry; D005638:Fruit / Q000737:chemistry; D017705:Lignans / Q000032:analysis* / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D010865:Pilot Projects; D010936:Plant Extracts / Q000737:chemistry*; D010946:Plants, Medicinal / Q000737:chemistry; D011083:Polycyclic Compounds / Q000032:analysis / Q000737:chemistry; D032141:Schisandra / Q000737:chemistry*; D012680:Sensitivity and Specificity; D014466:Ultraviolet Rays
chemical_list: D034242:Cyclooctanes; D004149:Dioxoles; D017705:Lignans; D010936:Plant Extracts; D011083:Polycyclic Compounds; C015499:schizandrin B; C033585:schizandrol B; C011105:schizandrin