Drug hydrate systems and dehydration processes studied by terahertz pulsed spectroscopy

  • Zeitler J
  • Kogermann K
  • Rantanen J
 et al. 
  • 55


    Mendeley users who have this article in their library.
  • 89


    Citations of this article.


Terahertz pulsed spectroscopy was used to distinguish between different hydrate systems. In the example of four pharmaceutical materials lactose, carbamazepine, piroxicam and theophylline it was demonstrated that all different hydrate and anhydrate forms exhibit distinct spectra in the far infrared. Furthermore the dehydration of theophylline monohydrate was characterised in situ. Here, a phase transition from the monohydrate to the anhydrous form was observed, followed by evaporation of the hydrate water in a second step. The rotational spectrum of water vapour is very characteristic in the far infrared and can easily be discerned from the terahertz spectrum of the solid state form. © 2006 Elsevier B.V. All rights reserved.

Author-supplied keywords

  • Dehydration
  • Hydrate forms
  • Phase transition
  • Principal components analysis
  • Terahertz pulsed spectroscopy (TPS)
  • Theophylline monohydrate

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Get full text


  • J. Axel Zeitler

  • Karin Kogermann

  • Jukka Rantanen

  • Thomas Rades

  • Philip F. Taday

  • Michael Pepper

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free