液相色谱法测定贝前列素钠异构体比率

Isomer ratio Dissolve 10 mg of Beraprost Sodium in 5 mL of methanol, and use this solution as the sample solution.Perform the test with 15 mL of the sample solution as directed under Liquid Chromatography <2.01> according to the following conditions, and determine the areas, Aa of the peak which appears at the retention time about 25 minutes, and Ab of the peak which appears at about 27 minutes: Ab/Aa is between 0.90 and 1.10.
Operating conditions—
    Detector: An ultraviolet absorption photometer (wavelength:285 nm).
    Column: A stainless steel column 6 mm in inside diameter and 15 cm in length, packed with octadecylsilanized silica gel for liquid chromatography (5 mm in particle diameter).
    Column temperature: A constant temperature of about 40℃.
    Mobile phase: A mixture of methanol, water and acetic acid (100) (600:400:1).
    Flow rate: Adjust so that the retention time of the second eluting peak of beraprost is about 27 minutes.
System suitability—
    System performance: When the procedure is run with 15 μL of the sample solution under the above operating conditions, the resolution between the two peaks of beraprost is not less than 1.2.
    System repeatability: When the test is repeated 6 times with 15 μL of the sample solution under the above operating conditions, the relative standard deviation of the total area of the two peak of beraprost is not more than 2.0%.