Carbamazepine polymorphism: A re-visitation using Raman imaging


Raman imaging methods have appeared in the last years as a powerf u l approach to monitoring the qualit y of pharmaceutical compounds. Because polymorphism occurs in many crystalline pharmaceutical compounds, it is essential to monitor polymorphic transformations induced by different external stimulus, such as temperature changes, to which those compounds may be submitted. Raman imaging with k-means cluster analysis (CA) is used here as an essential technique to investigate structural and chemical transformations occurring in carba-mazepine p-monoclinic (CBZ III) into carbamazepine triclinic (CBZ I) when submitted to temperatures near the melting point of CBZ III (178 ?degrees C) and CBZ I (193 ?degrees C).CBZ II I commercial powder and laboratorial prepared CBZ I were analyzed by differential scanning calo-rimetry, powder X-ray diffraction and Raman spectroscopy with variable temperature. After thermal treatment, the resultant CBZ powder was evaluated by Raman imaging, in which a l l imaging data was analyzed using CA . Raman imaging allowed the identification of different polymorphs of CBZ (CBZ I I I and CBZ I ) and iminostilbene (IMS), a degradation product of CBZ, in the treated samples, depending on the heatin g treatment method.



subject category

Pharmacology & Pharmacy


Fateixa, S; Nogueira, HIS; Trindade, T

our authors


Acknowledgement This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 & UIDP/50011/2020, financed by national funds through the FCT/MEC and when appropriate cofinanced by FEDER under the PT2020 Partnership Agreement. S. F. thanks FCT for his research contract (REF-069-88-ARH-2018) which is funded by national funds (OE) , through FCT-Fundacao para a Ciencia e aTecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5, and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19.

Share this project:

Related Publications

We use cookies for marketing activities and to offer you a better experience. By clicking “Accept Cookies” you agree with our cookie policy. Read about how we use cookies by clicking "Privacy and Cookie Policy".