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In this paper,high performance liquid chromatography(HPLC)along with mass spectrometry (MS)and HPLC along with a diode array detector(DAD)was used to study the compound flex pubescens extract.Two ionization techniques:electro spray ionization(ESI)and atmospheric pressure chemical ionization(APCI)were used in this work.The liquid chromatograms obtained by DAD,total ion chromatograms(TIC)from positive-and negative-ion ESI-MS and the positive-and negative-ion APCI-MS were compared.The liquid chromatograms obtained by TIC from ESI-MS provided more information on chromatographic peaks than those obtained by DAD or TIC from APCI-MS.It is suggested that the fingerprints of the compound Ilex pubescens extract should be provided by the liquid chromatograms obtained by DAD together with TIC from the negative-ion ESI-MS.The molecular weights of the nine main components in an HPLC-DAD chromatogram were determined by the corresponding positive-and negative-ion ESI and the positive-and negative-ion APCI mass spectra information.In the liquid chromatogram obtained by TIC from the negative-ion ESI-MS,the molecular weights of 23 main components were determined based on the corresponding positive-and negative-ion ESI mass spectra information.