Objective: To establish an UPLC-MS method for determination of antidiabetic drugs in Wentangan capsule. Method: Ultra performance liquid chromatography tandem quadrupole mass spectrometer was adopted

LC condition: A agela Venusil-C18 (2.1 mm×50 mm

3 μm) column was used with the isocratic elution of acetonitrile and 0.01 mol·L-1 ammonium acetate at a flow rate of 0.2 mL·min-1. MS condition: adopted electrospray ionization (ESI)

and multiple reaction monitoring (MRM); monitoring by ion-pairs: repaglinide (453.4→86.0

453.4→230.3)

glimepiride (491.4→126.2

491.4→352.3)

glibenclamide (494.2→168.5

494.2→368.9)

pioglitazone (357.2→119.0

357.2→134.1)

gliclazide (342.2→90.9

324.2→109.9)

glipizide (446.2→92.6

446.2→102.6)

phenethylbiguanide (206.2→59.7

206.2→104.6)

dimethyl biguanide (130.1→60.0

130.1→71.0). The retention time and relative intensities of the detected qualitative ion pairs using for qualitative

integrating the signals of the detected quantitative ion pairs using for quantitative. Result: The eight kinds of antidiabetic drugs had good linearity with correlation coefficient>0.999

ranging from 4.056-129.792

13.912-125.184

3.92-125.44

3.944-126.208

4.056-129.792

4.232-135.424

4.072-130.304 and 4.264

136.448 ng·L-1 respectively. The average recoveries were 98.18-100.95%. Repeatability experiments showed that RSD values of content were less than 2.95%. Conclusion: This method is reliable

simple and rapid with qualitative and quantitative accuracy

can be used for determination of antidiabetic drugs illegally added in Wentangan capsule.