Amlodipine mesylate monohydrate preparation method therefor and use thereof

A method for preparing an amlodipine mesylate monohydrate, wherein said method comprises following steps:

• dissolving an amlodipine free base in a water-containing organic solvent and adding methanesulfonic acid dropwise under low temperature condition to give a saturated solution, stirring and adding a seed crystal of amlodipine mesylate monohydrate thereto, adding methanesulfonic acid dropwise continuously under stirring to give crystals, growing the crystals, centrifuging, washing and vacuum drying before obtaining;
• wherein the organic solvent is one or more selected from the group consisting of ethyl acetate, acetone, acetonitrile and isopropanol;
• a molar ratio between the water contained in the organic solvent and the amlodipine free base is 1.0-10.0;
• a ratio (m:v) between the amlodipine free base and the organic solvent is 1:3-1:15;
• a total amount of methanesulfonic acid added is 0.9 to 2.0 equivalents of the amlodipine free base;
• an amount of methanesulfonic acid added before adding the seed crystal of amlodipine mesylate monohydrate is 10%-30% (mass percentage) of the total amount of methanesulfonic acid added;
• the low temperature condition is 0° C.-30° C.;
• the growing of the crystals is conducted under a temperature of −10° C.-30° C.;
• the growing of the crystals is conducted for 0.5-24 hours;
• a stirring rate utilized before the adding of the seed crystal is 150-200 rpm/min, and a stirring rate utilized after the adding of the seed crystal is 100 rpm/min-60 rpm/min;
• and
• the monohydrate is in crystal form, the crystal has a particle size distribution of D10:
• 20-40 μm, D50:
• 55-85 μm, D90:
• 95-140 μm, a carr index of 10-25%, an angle of repose (α) of 15-35°, a bulk density of 0.25-0.45 g/mL, and a purity of more than 99.5%.