Accelerated Degradation Experiment
30 days exposure at 50 °C and 100% relative humidity.
30 days exposure at 50 °C and 100% relative humidity followed by 4 days at 70 °C and 100% relative humidity.
Appearance of the substance
The substance, originally in the form of a white or almost white, crystalline powder remains unchanged after procedure A, but changes into a solid, pale yellow mass after procedure B.
Gain of moisture
After procedures A and B:
Adsorbent: Silica gel F-254
Solution applied to the plate: Substance dissolved in chloroform.
cyclohexane ............... 7 volumes
acetone ...................... 3 volumes
Development conditions: The solvent is allowed to migrate until the front reaches a line 15 cm from the starting line.
Detection: The plate is left in a chromatographic chamber containing some iodine crystals until spots appear.
Results: The spots obtained from the solution of the sample subjected to procedure A and the spots obtained from the reference solution of tolbutamide display the same chromatographic characteristics of migration and detection. No secondary spots are revealed. After procedure B, two additional spots are revealed that are less mobile than the main spot.
Prepare an aqueous suspension.
After procedure A: 4.8
After procedure B: 7
Tolbutamide is subject to decomposition under accelerated degradation conditions.