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 colourless or slightly yellowish crystals or a white or slightly yellowish, crystalline powder, changes after procedure A into a slightly yellowish powder and after procedure B into a hard orange brown mass.
Gain of moisture
After procedures A and B: 1%
Adsorbent: Silica gel F-254
Solution applied to the plate: Substance dissolved in chloroform.
Solvent system: chloroform
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 ergocalciferol display the same chromatographic characteristics of migration and detection, though some of the spots are slightly more intense. The degradation was assessed at less than 5%. After procedure B, additional spots, some more mobile and some less mobile than the main spot, are revealed, indicating gross degradation. The degradation was assessed at about 40%.
Ergocalciferol is subject to slight decomposition after procedure A, but strong decomposition is observed after procedure B.