Structure and drug release in a crosslinked poly(ethylene oxide) hydrogel

Boris Y. Shekunov, Pratibhash Chattopadhyay, Henry H.Y. Tong, Albert H.L. Chow, J. Günter Grossmann

Research output: Contribution to journalArticlepeer-review

15 Citations (Scopus)


Hydrogels are a continuously expanding class of pharmaceutical polymers designed for sustained or controlled drug release. The structure and intermolecular interactions in such systems define their macroscopic properties. The aim of this study was to investigate the mechanism of swelling, drug impregnation, and drug release from poly(ethylene oxide) (PEO) gel crosslinked by urethane bonds. A combination of SAXS/ WAXS/SANS techniques enabled us to determine the phase transition between lamellar and extended gel network, and to apply different descriptions of crystallinity, based on lamellar and crystal lattice structures. It is shown that even low (1-7% w/w) loading of model drugs acetaminophen and caffeine, produced significant disorder in the polymer matrix. This effect was particularly pronounced for acetaminophen due to its specific ability to form complexes with PEO. The drug-release profiles were analyzed using a general cubic equation, proposed for this work, which allowed us to determine the gel hydration velocity. The results indicate that the release profiles correlate inversely with the polymer crystallinity.

Original languageEnglish
Pages (from-to)1320-1330
Number of pages11
JournalJournal of Pharmaceutical Sciences
Issue number5
Publication statusPublished - May 2007


  • Atomic force microscopy (AFM)
  • Drug loading
  • Hydration
  • Poly(ethylene oxide) gels
  • Polymer crystallinity
  • Release
  • Small- and wide-angle X-ray scattering (SAXS/WAXS)
  • Small-angle neutron scattering (SANS)


Dive into the research topics of 'Structure and drug release in a crosslinked poly(ethylene oxide) hydrogel'. Together they form a unique fingerprint.

Cite this