Content Determination of Preservatives and Sweeteners in Oral Liquid Preparations by HPLC

OBJECTIVE To establish an HPLC method for determining the contents of preservatives and sweeteners in oral liquid preparations. METHODS The ZORBAX SB-C₁₈ chromatographic column(4.6 mm×250 mm, 5 μm) was adopted. The mobile phase was methanol-0.02 mol·L^-1 ammonium acetate solution with the gradient elution at the flow rate of 1.0 mL·min^-1. The detective wavelength was 240 nm, and the column temperature was 25 ℃. RESULTS Good resolution and linear correlation of acesulfame potassium, benzoic acid, sorbic acid, saccharin sodium, dehydroacetic, methylparaben, ethylparaben, propylparaben and butyl-p-hydroxybenzoate were found in the range of 5-100 μg·mL^-1(r>0.999). The detection limit of every components were 0.02, 0.04, 0.01, 0.10, 0.06, 0.01, 0.01, 0.01, 0.01 μg·mL^-1. The recovery range was 90.0%-110.0%. The instrument precision and repeatability were <2.0%(n=6). CONCLUTION This method is simple, reliable and accurate for determining the contents of preservatives and sweeteners in oral liquid preparation.