Objective: A method was established for the determination of five inorganic anions (F-

Cl-

NO-2

NO-3

PO3-4) in Gentiana rigescens by ultrasonic assisted extraction-ion chromatography. Method: The effects of the sampling volume

eluent proportion

flow rate and column temperature on the separation of the anions were investigated. The effects of deionized water and NaOH (3.0 mmol ·L-1) in different extraction time were also investigated. Result: Under the following chromatographic conditions:sampling volume of 100 μL

eluent of Na2CO3+ NaHCO3(3.50 mmol ·L-1+1.0 mmol ·L-1)

flow rate of 1.2 mL ·min-1

column temperature of 30 ℃ for F-

Cl-

NO-2

NO-3 and PO3-4

the detection limits of 5 anions were 0.097 6-1.098 4 mg ·L-1

the linear range of the calibration curves were 2-25 mg ·L-1

2-20 mg ·L-1

2-100 mg ·L-1

10-55 mg ·L-1 and 40-100 mg ·L-1

the relative standard deviations (RSD) of the peak height were 0.98%

1.20%

0.77%

0.87%

2.26%

and the RSD of the peak width were 0.58%

1.27%

0.73%

0.92%

2.33%. With extraction for 30 min by NaOH (3.0 mmol ·L-1)

centrifuging with 10 000 r ·min-1for 20 min

and filtration by 0.45 μm filter membrane

for F-

Cl-

NO-3 and PO3-4

the spike recovery were 110.38%

106.18%

96.47%

117.23%

whereas

the spike recovery of NO-2 was not detected. Conclusion: It is satisfied with using this method to determine the content of 5 anions in different parts of G. rigescens.