Determination of the Related Substances and Content in the Complex System of Latanoprost Eye Drops by HPLC

OBJECTIVE To develop an HPLC method for the determination of the related substances and content in the complex system of Latanoprost Eye drops. METHODS the conditions of detection were Sugar Chiral column C₁₈(250 mm×4.6 mm, 5 μm), related substances measured using the isocratic mobile phase consisted of 0.005 mmol·L^-1 sodium dihydrogen phosphate (adjust with phosphate to pH 2.7)-acetonitrile(56:44), and the mobile phase for content determination was 0.005 mol·L^-1 sodium dihydrogen phosphate solution (adjusted with phosphoric acid to pH 2.7)-acetonitrile(54:46) with a flow rate of 0.5 mL·min^-1, the UV detection wavelength was 200 nm. RESULTS The resolution of 5, 6-trans-Latanoprost and 15S-Latanoprost was good. the method for determination of the related substances of Latanoprost Eye drops had a good linearity. The average recovery of 5,6-trans-Latanoprost and 15S-Latanoprost were 101.5% and 99.5%. The limit of quantitation of Latanoprost, 5,6-trans-Latanoprost and 15S-Latanoprost were 0.12, 0.13 and 0.12 μg·ml^-1. The method for determination of Latanoprost Eye drops had a good linearity, the repeatability was good (RSD=0.90%). The average recovery of Latanoprost was 98.8%. CONCLUSION The method is accurate and reliable, which can be used to control the quality of Latanoprost Eye drops.