An ultra high performance liquid chromatography coupled with linear ion trap-orbitrap mass spectrometric(UPLC-LTQ-Orbitrap-MS) method was developed for the qualitative analysis of main chemical constituents in Duzhong granules

a Chinese medicine.The sample was ultrasonically extracted with methanol

then separated on a Thermo Scientific Syncronis C18 chromatographic column(100 mm×21 mm

19 μm) by gradient elution with acetonitrile-01% formic acid as mobile phase.The data were collected by using LTQ-Orbitrap-MS in negative ion mode.According to the contrast of the reference standards and the accurate masses of molecules

a total of 25 compounds in Duzhong granules were identified

including 8 iridoids

8 flavonoids

5 phenylpropanoids

3 lignans and 1 non reducing disaccharide.Results showed that

with the advantages of simplicity

rapidness and accuracy

the developed method was suitable for the identification of chemical constituents in Duzhong granules

which provided a reference for the pharmacological basis of further analysis of Duzhong granules.