Enzyme-responsive hydrogel particles for the controlled release of proteins: designing peptide actuators to match payload

Paul D. Thornton, Robert J. Mart, Simon J. Webb, Rein V. Ulijn

Research output: Contribution to journalArticlepeer-review

110 Citations (Scopus)


We report on enzyme-responsive hydrogel particles for the controlled release of proteins. Amino-functionalised poly(ethylene glycol acrylamide) (PEGA) hydrogel particles were functionalised with peptide actuators that cause charge-induced swelling and payload release when triggered enzymatically. Peptide-based actuators were designed to match the specificity of the target enzyme, while also matching the charge properties of the to-be released protein payload, thereby uniquely allowing for tuneable release profiles. Fluorescently labelled albumin and avidin, proteins of similar size but opposite charge, were released at a rate that was governed by the peptide actuator linked to the polymer carrier, offering a highly controlled release mechanism. Release profiles were analysed using a combination of fluorescence spectroscopy of the solution and two-photon fluorescence microscopy to analyse enzymatically triggered molecular events within hydrogel particles during the initial stages of release.

Original languageEnglish
Pages (from-to)821-827
Number of pages7
JournalSoft Matter
Issue number4
Early online date8 Feb 2008
Publication statusPublished - 2008


  • enzyme-responsive
  • hydrogel particles
  • controlled release
  • proteins
  • peptide actuators
  • match payload

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