Determination of 14 kinds of amino acids in Wuling Capsule by HPLC-FLD / 中成药

ABSTRACT

AIM: To establish an analytical method for detecting 14 kinds of amino acid in Wuling Capsule(xylaria) by HPLC-FLD. METHODS: After being derivated in precolumn with o-phthalaldehyde and ?-mercaptoethanol,the amino acids were eluted by gradient elution and were detected with a fluorescence detector (Ex = 340 nm,Em = 450 nm). The mobile phase consisted of 0. 1 mol/L NaH2PO4 ( adjusted to pH 6. 8 by phosphoric acid) and methanol with a flow rate of 1. 0 mL/min,column temperature was set at 30 ℃. RESULTS: The deriva-tives of 14 amino acids with o-phthalaldehyde could be separated with a stable base line within 40 min. The linear range of the detection was 5-200 nmol/mL and correlation coefficients were over 0. 999 0. CONCLUSION: The method is simple,accurate and well reproduced for the determination of amino acids in Wuling Capsule.