(1986; 119 pages)
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 5 days at 70 °C and 100% relative humidity.
Appearance of the substance
The substance, originally in the form of a white, fine crystalline powder, changes after procedure A into a solid, pale yellow mass and after procedure B into a solid, orange-coloured mass.
Gain of moisture
After procedures A and B:
Adsorbent: Silica gel F-254
Solution applied to the plate: Substance dissolved in ethane 95%.
n-butanol ........... 6 volumes
acetic acid ......... 2 volumes
water ................. 2 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 solutions of each of the samples subjected to procedures A and B, compared to the spots obtained from the reference solution of phenoxymethylpenicillin are more intense and more numerous.
Phenoxymethylpenicillin is subject to decomposition under accelerated degradation conditions.