Applications of HPLC-MS in compound Ilex pubescens extract study

Abstract

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 Ilex 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.