Direct laser writing of synthetic poly(amino acid) hydrogels and poly(ethylene glycol) diacrylates by two-photon polymerization

Research output: Contribution to journalArticleScientificpeer-review


  • Elli Käpylä
  • Tomáš Sedlačík
  • Dogu Baran Aydogan
  • Jouko Viitanen
  • František Rypáček
  • Minna Kellomäki

Research units

  • Tampere University of Technology
  • BioMediTech Finland
  • Czech Academy of Sciences
  • VTT Technical Research Centre of Finland


The additive manufacturing technique of direct laser writing by two-photon polymerization (2PP-DLW) enables the fabrication of three-dimensional microstructures with superior accuracy and flexibility. When combined with biomimetic hydrogel materials, 2PP-DLW can be used to recreate the microarchitectures of the extracellular matrix. However, there are currently only a limited number of hydrogels applicable for 2PP-DLW. In order to widen the selection of synthetic biodegradable hydrogels, in this work we studied the 2PP-DLW of methacryloylated and acryloylated poly(α-amino acid)s (poly(AA)s). The performance of these materials was compared to widely used poly(ethylene glycol) diacrylates (PEGdas) in terms of polymerization and damage thresholds, voxel size, line width, post-polymerization swelling and deformation. We found that both methacryloylated and acryloylated poly(AA) hydrogels are suitable to 2PP-DLW with a wider processing window than PEGdas. The poly(AA) with the highest degree of acryloylation showed the greatest potential for 3D microfabrication.


Original languageEnglish
Pages (from-to)280-289
Number of pages10
JournalMaterials Science and Engineering C
Publication statusPublished - 1 Oct 2014
MoE publication typeA1 Journal article-refereed

    Research areas

  • Direct laser writing, Hydrogel, Microfabrication, Poly(ethylene glycol) diacrylate, Polyamino acid, Two-photon polymerization

ID: 29135177