Hydrogels: from controlled release to pH-responsive drug delivery

Drug Discov Today. 2002 May 15;7(10):569-79. doi: 10.1016/s1359-6446(02)02255-9.


Hydrogels are one of the upcoming classes of polymer-based controlled-release drug delivery systems. Besides exhibiting swelling-controlled drug release, hydrogels also show stimuli-responsive changes in their structural network and hence, the drug release. Because of large variations in physiological pH at various body sites in normal as well as pathological conditions, pH-responsive polymeric networks have been extensively studied. This review highlights the use of hydrogels (a class of polymeric systems) in controlled drug delivery, and their application in stimuli-responsive, especially pH-responsive, drug release.

Publication types

  • Review

MeSH terms

  • Delayed-Action Preparations* / chemistry
  • Humans
  • Hydrogels* / chemistry
  • Hydrogen-Ion Concentration*
  • Models, Theoretical
  • Pharmaceutical Preparations / administration & dosage*


  • Delayed-Action Preparations
  • Hydrogels
  • Pharmaceutical Preparations