title: [Vectorial angle method for evaluating the similarity between two chromatographic fingerprints of Chinese herb].
abstract: OBJECTIVE
  To evaluate the similarity between two chromatographic fingerprints automatically with computer.
  
  
  METHODS
  Chromatogram can be treated as vector of hyperspace, and the similarity between them can be counted according to vectorial angle formula. This process was performed with software written in Visual Basic 6.0. The two main functions of this software are automatic peak tracking in two fingerprints under the same analytic condition and computing the similarity automatically.
  
  
  RESULTS
  The HPLC fingerprints of eleven kinds of Evodia rutaecarpa (Juss.) Benth (a traditional Chinese herb) from different sources were obtained and the similarities were calculated with this software. This method was shown to be a good way to evaluate the similarity between two fingerprints. A sample washed seven times with hot water can be clearly discriminated from other samples of Evodia rutaecarpa (Juss.) Benth with similar results.
  
  
  CONCLUSIONS
  This method is a good way to evaluate the similarity between two fingerprints and is helpful in quality control of traditional Chinese medicine.
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116012, China. wanglx@ms.dicp.ac.cn
authors.forename: Long-xing
authors.initials: LX
authors.lastname: Wang
authors.forename: Hong-bin
authors.initials: HB
authors.lastname: Xiao
authors.forename: Xin-miao
authors.initials: XM
authors.lastname: Liang
authors.forename: Kai-shun
authors.initials: KS
authors.lastname: Bi
mesh_terms: D032086:Evodia / Q000737:chemistry* / Q000145:classification; D010946:Plants, Medicinal / Q000737:chemistry*; D011786:Quality Control; D012985:Software Design