Determination of Benzoic Acid and Cinnamic Acid in Suhexiang Pills by HPLC with Dual Wavelength De-tection / 中国药师

ABSTRACT

Objective:To establish an HPLC method with dual wavelength detection for the determination of benzoic acid and cin-namic acid in Suhexiang pills. Methods:A Waters Sun Fire TM C18 column(150 mm × 4. 6 mm,5 μm) was adopted with 0. 1% ace-tic acid-methanol(60∶40) as the mobile phase at a flow rate of 1. 0 ml·min-1 . The detection wavelength was set at 228nm for benzoic acid(0-18min) and 285nm for cinnamic acid (18. 1-35min). The injection volume was 10μl, and the column temperature was room temperature. Results:The linear range of benzoic acid and cinnamic acid was 1. 0-50. 0 μg·ml-1(r=0. 999 7) and 0. 2-10. 0 μg· ml-1, respectively(r=0. 999 9). The average recovery was 96. 88%(RSD=1. 6%, n=9) and 99. 35%(RSD=1. 7%, n=9), re-spectively. Conclusion:The method is accurate, fast and simple in the determination of benzoic acid and cinnamic acid in Suhexiang pills.