ABSTRACT
To establish an HPLC method for the determination of impurity Ⅰ and impurity Ⅱ in latanoprost eye drop.HPLC separation was carried on a Zorbax SB-C1s column (4.6 mm250 mm,5 m) with the mobile phase consisting of methanol-acetonitrile-water (adjusting pH to 3.0 with acetic acid) (56 ∶ 14 ∶ 30).The flow rate was 1.0 mL/min;the detection wavelength was 210 nm;and the injection volume was 100 μL.Impurity Ⅰ,impurity Ⅱ and latanoprost were separated efficiently under the selected HPLC conditions,with good linearity in the range of 0.049 99-0.999 8 g/mL for impurity Ⅰ and 0.049 94-0.998 8 g/mL for impurity II.The average recoveries of impurity Ⅰ and Ⅱ were 96.74％ (n =9) and 94.99％ (n =9),respectively.The established method can be used for the detection of stereoisomers in latanoprost eye drop.