METHOD FOR PREPARING DRUG COMPOSITION BASED ON INCREASING ACTIVE AGENT AFFINITY OF CRYSTALLINE MICROPARTICLE SURFACES Russian patent published in 2012 - IPC A61K9/16 A61K38/28 A61K38/27 A61K47/22 A61K47/30 A61J3/00 

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention refers to a crystalline microparticle for deliverying active agents which contains diketopiperazine and polysorbate 80. The invention also refers to a method for making said microparticle. The method involves the stages for preparing a diketopiperazine solution with limited solubility and low pH value, adding polysorbate 80 to the solution and precipitating diketopiperazine microparticles at the stages of adding acid to the solution. The invention also refers to a method of coating the pre-formed said microparticle. The method involves producing a suspension containing the pre-formed crystalline microparticle, the active agent and the solvent, changing the suspension properties for controlling power interaction between the specified active agent and pre-formed crystalline microparticle and absorbing the active agent on the microparticle surface for the purpose of coating. The stage of changing the properties and the stages of absorbing proceed without removing the solvent from the suspension.

EFFECT: invention provides making stable particles whereto the active agent has higher affinity than to the solution wherein is found.

15 cl, 8 dwg, 4 tbl, 7 ex