Amorphism and physicochemical stability of spray-dried frusemide.
The physicochemical properties of amorphous forms of frusemide, prepared by spray-drying at 50 or 150 degrees C, and their hygroscopic stability at temperatures of 25 and 40 degrees C, and at 0 and 75% relative humidity were investigated. The glass transition temperature of the amorphous form A was 44.2 degrees C as measured by differential scanning calorimetry, while that of the amorphous form B was 54.4 degrees C. The activation energies for glass transition and crystallization processes were calculated from the differential scanning calorimetry thermograms of amorphous forms A and B, respectively. Stability determined by X-ray diffraction at 0% relative humidity, 25 and 40 degrees C suggested that form B was more stable than form A. However, the stability of form A at 75% relative humidity and 25 and 40 degrees C was similar to that of form B.
Department of Pharmaceutical Technology, Kobe Women's College of Pharmacy, Japan.
Y
Y
Matsuda
M
M
Otsuka
M
M
Onoe
E
E
Tatsumi
D004355:Drug Stability; D005665:Furosemide / Q000737:chemistry*; D006813:Humidity; D013055:Spectrophotometry, Infrared; D013696:Temperature; D014961:X-Ray Diffraction
D005665:Furosemide