HPLC Determination of Salicylic Acid in Food Additives

HPLC was applied to the determination of salicylic acid in food additives. The sample was dissolved with mixed solvent of methanol-H2O (9+1) (containing 0.1% formic acid by vol.) and extracted ultrasonically. After filtering on 0.22 μm filtering membrane, the solution was used for HPLC analysis. The ZORBAX SB-C18 chromatographic column (4.6 mm×250 mm, 3.5 μm) was used for separation and a mixture of (A) formic acid-acetonitrile (0.1+99.9) and (B) formic acid (0.1+99.9)solution mixed in different ratio were used as the mobile phase in gradient elution. Fluorimetric detection at the wavelengths of (λex) 280 nm and (λem) 450 nm was adopted. Linear relationship between values of peak area and mass concentration of salicylic acid was obtained in the range of 41.60~1 664 μg·L-1, with detection limit (3S/N) of 1.55 μg·L-1. Values of recovery of the method found were in the range of 90.4%-101.7%.