Journal Article


Andrea Erxleben
Patrick McArdle
Clare M. Crowley
Pól MacFhionnghaile



relative humidity co crystallization calorimetry differential scanning caffeine data analysis x ray diffraction powder x ray room temperature

Spontaneous solid-state co-crystallization of caffeine and urea (2020)

Abstract The full text of this article will not be available in ULIR until the embargo expires on the 09/01/2021 The co-crystallization of caffeine and urea was monitored and analyzed using infrared spectroscopy, Raman microscopy, scanning electron microscopy, differential scanning calorimetry and X-ray diffraction. The caffeine-urea co-crystal was shown to form spontaneously over several weeks under low energy mixing of the solids at room temperature and low relative humidity (<30%). Pre-milling the two coformers separately accelerated the process and the co-crystal formation could be detected within three days. When caffeine and urea were milled together, the physical mixture that was confirmed by X-ray powder diffraction immediately after milling transformed to the co-crystal within hours of storage at room temperature and 30 % relative humidity. The scanning electron microscopy images of the milled sample indicated the role of inter-particle surface contact in the spontaneous solidstate reaction. Multivariate data analysis was used to find the optimum cooling crystallization conditions for obtaining co-crystals suitable for single crystal X-ray analysis.
Collections Ireland -> University of Limerick -> Synthesis and Solid State Pharmaceutical Centre
Ireland -> University of Limerick -> Centres Science and Engineering
Ireland -> University of Limerick -> Faculty of Science and Engineering

Full list of authors on original publication

Andrea Erxleben, Patrick McArdle, Clare M. Crowley, Pól MacFhionnghaile

Experts in our system

Andrea Erxleben
University of Limerick
Total Publications: 10
Patrick McArdle
National University of Ireland Galway
Total Publications: 23
Clare M. Crowley
University of Limerick
Total Publications: 5