ABSTRACT
OBJECTIVE: To establish a method for the determination the contents of dimethyl phthalate (DMP), diethyl phthalate (DEP) and dibutyl phthalate (DBP) in lansoprazole enteric-coated capsules. METHODS: Based on RP-HPLC/UV, the method used C18 column (4.6 mm × 250 mm, 5 μm) for separation, methanol-water (75: 25) as mobile phase for isocratic elution and detection wavelength 230 nm. RESULTS: The quantification of diethyl phthalate in four batches of lansoprazole enteric-coated capsules was carried. The concentration and UV peak area with a good linear relationship within the following: the linear equation of DMP was Y = 48.848ρ - 2.8112 (r = 0.9999) in range of 1.4 - 14 μg · mL-1, the linear equation of DEP was Y = 67.619ρ - 30.754 (r = 0.9990) in the range of 1.36 - 20.4 μg · mL-1. The linear equation of DBP was Y = 36.759X - 4.8507 (r = 0.9999) in the range of 1.5 - 15.5 μg · mL-1. The sample recovery of DMP, DEP and DBP was 91.3%, 96.1% and 94.7%. The RSD of sample recovery was 2.9%, 4.4% and 4.7%. CONCLUSION: The method is simple, sensitive and with a strong anti-interference ability. It can determination accurately the contents of DMP, DEP and DBP in lansoprazole enteric-coated capsules. Copyright 2012 by the Chinese Pharmaceutical Association.