Enzymatic Crosslinking of Polymer Conjugates is Superior over Ionic or UV Crosslinking for the On-Chip Production of Cell-Laden Microgels

Research output: Contribution to journalResearch articleContributedpeer-review


  • Sieger Henke - , University of Twente (Author)
  • Jeroen Leijten - , University of Twente (Author)
  • Evelien Kemna - , University of Twente (Author)
  • Martin Neubauer - , University of Bayreuth (Author)
  • Andreas Fery - , Chair of Physical Chemistry of Polymeric Materials, Leibniz Institute of Polymer Research Dresden (Author)
  • Albert van den Berg - , University of Twente (Author)
  • Aart van Apeldoorn - , University of Twente (Author)
  • Marcel Karperien - , University of Twente (Author)


Cell-laden micrometer-sized hydrogels (microgels) hold great promise for improving high throughput ex-vivo drug screening and engineering biomimetic tissues. Microfluidics is a powerful tool to produce microgels. However, only a limited amount of biomaterials have been reported to be compatible with on-chip microgel formation. Moreover, these biomaterials are often associated with mechanical instability, cytotoxicity, and cellular senescence. To resolve this challenge, dextran-tyramine has been explored as a novel biomaterial for on-chip microgel formation. In particular, dextran-tyramine is compared with two commonly used biomaterials, namely, polyethylene-glycol diacrylate (PEGDA) and alginate, which crosslink through enzymatic reaction, UV polymerization, and ionic interaction, respectively. Human mesenchymal stem cells (hMSCs) encapsulated in dextran-tyramine microgels demonstrate significantly higher (95%) survival as compared to alginate (81%) and PEGDA (69%). Long-term cell cultures demonstrate that hMSCs in PEGDA microgels become senescent after 7 d. Alginate microgels dissolve within 7 d due to Ca2+ loss. In contrast, dextran-tyramine based microgels remain stable, sustain hMSCs metabolic activity, and permit for single-cell level analysis for at least 28 d of culture. In conclusion, enzymatically crosslinking dextran-tyramine conjugates represent a novel biomaterial class for the on-chip production of cell-laden microgels, which possesses unique advantages as compared to the commonly used UV and ionic crosslinking biomaterials. (Figure presented.).


Original languageEnglish
Pages (from-to)1524-1532
Number of pages9
JournalMacromolecular bioscience
Issue number10
Publication statusPublished - 1 Oct 2016

External IDs

PubMed 27440382



  • biomaterials, enzymatic, hydrogel, microfluidic, microgels