Cryomodification of drugs: Micronized amorphous state of carvedilol

By means of cryochemical modification, including substance evaporation in a stream of a heated gas-carrier with subsequent condensation of vapor on a surface, cooled up to the boiling temperature of liquid nitrogen (?196°C), the X-ray amorphous state of the drug carvedilol, (±)-1-(9H-carbazole-4-iloxy)-3-[2-(2-methoxyphenoxy)-ethylamino]propane-2-ol, was obtained. It is shown that, along with amorphization, cryomodification leads to micronization of the drug—the sizes of its particles decrease from an initial 5–10 up to 1–2 μm.