Molecular Weight and Molecular Weight Distribution Put appropriate of this product (equivalent to 50 mg iron), add 4 mol/L sodium dihydrogen phosphate solution 1 ml, shake well, place quietly for the night, add water to 10 ml, filtered, filtrate renewal as a solution of the test. Take 4 ~ 5 other known molecular weight dextran reference substance, add mobile phase to dissolve and diluting to each 1 ml containing 10 mg(Fe) of the solution as a reference substance solution. According to molecular exclusion chromatography USP38 With hydrophilic spherical polymer as a filler, determination of polysaccharide gel column, with 0.71% sodium sulfate solution (containing 0.02% sodium azide) as mobile phase, column temperature 35 ℃, the flow rate of 0.5 ml per minute, refractive index detector.
Weight the right amount of glucose and dextran 2000, plus mobile phase respectively dissolved and dilution, make each 1 ml contains about 10 mg of solution, Take 20µl inject into liquid chromatograph, measured retention time tT and t0; The chromatograph chart of test sample solution and reference solution in retention time of main peak tR shall be between tT and t0.Theoretical plate number calculated on glucose peak is not less than 5000.
Take the above reference substance solution 20µl, inject into liquid chromatograph respectively, record chromatograph chart, calculated the regression equation by the GPC proprietary software. Take 50µl sample solution, with determination, use GPC software to calculate the weight of molecular weight and molecular weight distribution of the test. This iron dextran’s molecular weight (Mw) should be LOW, the distribution coefficient D (Mw/Mn) should be less than 1.8.
Post time: Jun-05-2026
