Accelerated Degradation Experiment
Conditions
Procedure A: |
30 days exposure at 50 °C and 100% relative humidity. |
Procedure B: |
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 colourless crystals or a white, crystalline powder, changes after procedure A into a slightly yellow-coloured powder and after procedure B into a liquid that solidifies upon cooling.
Gain of moisture
Melting point
Before exposure to heat and humidity: |
156 °C |
After procedure B: |
154 °C |
Chromatographic test
Adsorbent: Silica gel F-254
Solution applied to the plate: Substance dissolved in methanol - water (9:1).
Solvent system:
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 solution of the sample subjected to procedure A and the spots obtained from the reference solution of procaine hydrochloride display the same chromatographic characteristics of migration and detection. After procedure B, tailing is observed below the main spot.
Conclusion
Procaine hydrochloride is subject to slight decomposition under accelerated degradation conditions.