Change search
ReferencesLink to record
Permanent link

Direct link
Thermodynamics and crystallization of a theophylline-salicylic acid cocrystal
KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Transport Phenomena. University of Limerick, Ireland.
2015 (English)In: CrystEngComm, ISSN 1466-8033, Vol. 17, no 22, 4125-4135 p.Article in journal (Refereed) Published
Abstract [en]

A 1: 1 theophylline-salicylic acid cocrystal has been successfully prepared by slurry conversion crystallization in a 1 : 1 molar ratio slurry of theophylline and salicylic acid in chloroform. The cocrystal powder was analysed by XRD and DSC, and the cocrystal structure was determined by single crystal XRD. The cocrystal melts at 188.5 degrees C, which is between the melting points of the pure cocrystal components. Microscopy and SEM images have been taken for the cocrystals prepared by slow evaporation from ethanol, ethyl acetate, or acetonitrile. The cocrystal dissolves congruently in chloroform and the solubility is determined. Based on the solubility data for the cocrystal and the pure components, the Gibbs free energy of cocrystal formation is calculated to be -4.92 kJ mol(-1) at 30 degrees C. The cocrystal dissolves incongruently in methanol, ethanol, and acetonitrile. The ternary phase diagram of the cocrystal in acetonitrile has been determined and compared with those of theophylline-oxalic acid and theophylline-glutaric acid cocrystal systems. By proper operation of the process in the phase diagram, the theophylline-salicylic acid cocrystal can be produced by slurry conversion crystallization in acetonitrile.

Place, publisher, year, edition, pages
2015. Vol. 17, no 22, 4125-4135 p.
Keyword [en]
Co-Crystal System, Pharmaceutical Cocrystal, Phase-Diagrams, State, Solubility, Stability, Polymorph, Salt
National Category
Chemical Sciences
URN: urn:nbn:se:kth:diva-169983DOI: 10.1039/c5ce00240kISI: 000355481800012ScopusID: 2-s2.0-84930225745OAI: diva2:827106
Swedish Research Council, 621-2007-3982

QC 20150626

Available from: 2015-06-26 Created: 2015-06-25 Last updated: 2015-06-26Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Zhang, ShuoRasmuson, Åke C.
By organisation
Chemical Engineering and TechnologyTransport Phenomena
In the same journal
Chemical Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 23 hits
ReferencesLink to record
Permanent link

Direct link