Liquid chromatograph mass spectrometer

Abstract

In a liquid chromatograph mass spectrometer, chromatogram data is obtained by carrying out alternately a mass scanning in a positive ion detection mode and a mass scanning in a negative ion detection mode, obtaining the chromatogram data in every positive and negative polarities through summing up the mass spectrum data obtained at the respective mass scannings, and adding the data of both polarities. Since the chromatograms in both polarities are averaged, even if there is a level difference therebetween, a chromatogram in a normal form can be obtained.

What is claimed is:  
     
         1 . A chromatograph mass spectrometer for sequentially processing a sample, comprising: 
 a setting device for setting beforehand a plurality of spectrometry conditions when a mass spectrometry is carried out,    a spectrometry execution device electrically connected to the setting device for executing a cycle of spectrometries by changing one of the spectrometry conditions set by the setting device whenever one mass scanning in said cycle is carried out, said spectrometry execution device sequentially executing the one cycle spectrometries repeatedly, and    an operation device electrically connected to the spectrometry execution device for obtaining chromatogram data by respectively adding together a number of mass spectrum data obtained by the one mass scanning in one cycle when one cycle of the mass spectrometry is completed.    
     
     
         2 . A chromatograph mass spectrometer according to  claim 1 , further comprising an introducing section for introducing the sample, a chromatograph portion connected to the introducing section f or separating components in the sample along a passage of time, a mass spectrometry portion connected to the chromatograph portion f or analyzing the components, and a fraction collector connected to the chromatograph portion for collecting the respective components based on information obtained in the mass spectrometry portion.  
     
     
         3 . A chromatograph mass spectrometer according to  claim 2 , further comprising a fraction control device electrically connected to the operation device for controlling an operation of the fraction collector based on the chromatogram data obtained by the operation device.  
     
     
         4 . A chromatograph mass spectrometer according to  claim 3 , wherein said operation device adds the chromatogram data at the one mass scanning with an added value in another mass scanning.  
     
     
         5 . A chromatograph mass spectrometer according to  claim 3 , wherein said operating device obtains the chromatogram data by adding the mass spectrum data with respect to a specific mass number obtained by each mass scanning.  
     
     
         6 . A chromatograph mass spectrometer according to  claim 1 , wherein said mass spectrometer is a liquid chromatograph mass spectrometer.