Drug release from thin films encapsulated by a temperature-responsive hydrogel

Oliver Werzer, Stephan Tumphart, Roman Keimel, Paul Christian, Anna Maria Coclite

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Control over drug delivery may be interestingly achieved by using temperature responsive encapsulants, which change their thickness and mesh size with temperature. The prototype N-isopropylacrylamide hydrogel cross-linked with di(ethylene glycol) divinyl ether p(NIPAAm-co-DEGDVE) swells at low temperature and collapses above the lower critical solution temperature (LCST), ∼29 °C in a buffer. It might be expected that drug release from such encapsulation is always favored below the LCST, due to the larger free volume present in the swollen polymer film. Recent results show contradicting behavior where some cases behave as expected and others release much less when the polymer layer is swollen. In this study, layers of the drugs phenytoin, clotrimazole and indomethacin were drop cast on glass and p(NIPAAM-co-DEGDVE) layers were then synthesized directly on top of these drug layers via initiated chemical vapor deposition (iCVD), a solvent-free and gentle polymerization technique. Dissolution experiments were then performed, in which the drug release through the hindrance of the hydrogel was measured at different pH values. The results show that not only the swelling but also the permeate (drug in this case)-polymer interaction plays an important role in the release.

Original languageEnglish
Pages (from-to)1853-1859
Number of pages7
JournalSoft matter
Volume15
Issue number8
DOIs
Publication statusPublished - 1 Jan 2019

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Hydrogel
drugs
Thin films
thin films
Pharmaceutical Preparations
Polymers
Temperature
temperature
polymers
Clotrimazole
Ethylene Glycol
Free volume
Phenytoin
Drug delivery
Encapsulation
Polymer films
Indomethacin
Swelling
Chemical vapor deposition
Buffers

ASJC Scopus subject areas

  • Chemistry(all)
  • Condensed Matter Physics

Cooperations

  • NAWI Graz

Cite this

Drug release from thin films encapsulated by a temperature-responsive hydrogel. / Werzer, Oliver; Tumphart, Stephan; Keimel, Roman; Christian, Paul; Coclite, Anna Maria.

In: Soft matter, Vol. 15, No. 8, 01.01.2019, p. 1853-1859.

Research output: Contribution to journalArticleResearchpeer-review

Werzer, Oliver ; Tumphart, Stephan ; Keimel, Roman ; Christian, Paul ; Coclite, Anna Maria. / Drug release from thin films encapsulated by a temperature-responsive hydrogel. In: Soft matter. 2019 ; Vol. 15, No. 8. pp. 1853-1859.
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