Vibrational Dynamics of Carbamazepine: Studies Based on Two-Dimensional Correlation Spectroscopy and X-ray
Agnieszka Dołęga1, Ewa Juszyńska-Gałązka1, Aleksandra Deptuch1
1Institute of Nuclear Physics Polish Academy of Sciences, Krakow, Poland.
Applied Spectroscopy
|November 14, 2019
Summary
Carbamazepine (CBZ) undergoes cold crystallization during heating, with X-ray diffraction revealing drug degradation products. Advanced spectroscopy techniques effectively mapped these phase transitions and degradation pathways.
Area of Science:
- Solid-state chemistry
- Pharmaceutical analysis
- Spectroscopy
Background:
- Carbamazepine (CBZ) is a vital antiepileptic drug.
- Understanding its thermal behavior is crucial for stability and formulation.
- Phase transitions can impact drug efficacy and safety.
Purpose of the Study:
- To investigate phase transitions of carbamazepine during a heating-cooling-heating cycle.
- To identify crystalline forms and degradation products.
- To evaluate advanced spectroscopic methods for analyzing phase transitions.
Main Methods:
- Fourier transform infrared spectroscopy (FTIR).
- X-ray diffraction (XRD).
- Moving window two-dimensional correlation (MW 2D-COS) spectroscopy.
- Two-dimensional correlation spectroscopy (2D-COS).
Main Results:
- Cold crystallization of carbamazepine was observed during the second heating phase.
- XRD confirmed the coexistence of carbamazepine (form I) and iminostilbene (degradation product) after thermal cycling.
- MW 2D-COS and 2D-COS spectroscopy effectively elucidated phase sequences and intensity changes.
Conclusions:
- The study demonstrates cold crystallization and degradation of carbamazepine under thermal stress.
- XRD provides crucial evidence for drug degradation products.
- 2D correlation spectroscopy techniques are powerful tools for detailed analysis of solid-state phase transitions.
Keywords:
2D-COSCarbamazepineFourier transform infrared spectroscopyX-ray diffractionXRDdegradationphase transitiontwo-dimensional correlation spectroscopyMore Related Videos
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