Journal of Thermal Analysis and Calorimetry

, Volume 105, Issue 3, pp 1023–1030 | Cite as

The development of a quick method for amorphicity determination by isothermal microcalorimetry

  • Miha Vivoda
  • Robert RoškarEmail author
  • Vojko Kmetec


This study presents a contribution in the development of a quick and accurate testing method for the determination of amorphous content using isothermal microcalorimetry. Examples demonstrated how the choice of the experimental conditions, especially sample load, temperature and humidity, influences the crystallization of the amorphous material. The suitability of this systematic approach was first tested on well-known lactose and afterwards on nifedipine as model compounds. It was shown that by proper method design and careful selection of experimental conditions, it is possible to achieve quick determination of the amorphous content in samples with a quantification limit of less than 1%, what is considerably better than by classical analytical methods such as DSC and XRPD. Our optimized microcalorimetry method gave also better results compared to previously reported literature data for nifedipine.


Microcalorimetry Amorphicity Lactose Nifedipine Physical stability 


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2011

Authors and Affiliations

  1. 1.Faculty of PharmacyUniversity of LjubljanaLjubljanaSlovenia

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