[Zurück]

P. Gruber, M. Markovic, M. Tromayer, S Mühleder, J. Van Hoorick, K. Hölzl, W Holnthoner, H. Redl, P. Dubruel, R. Liska, S. Van Vlierberghe, A. Ovsianikov:
"Laser photofabrication of 3D hydrogel structures within microfluidic channels";
Vortrag: International Conference on Biofabrication 2016, Winston-Salem, North Carolina, USA; 29.10.2016 - 31.10.2016; in: "Biofabrication 2016", elsevier, (2016), S. OP-16.

Two-photon polymerization (2PP) is a 3D printing approach based on femtosecond-laser- induced
polymerization. This technology allows one to produce complex CAD structures with remarkably high
spatial resolution. Furthermore, in contrast to other additive manufacturing technologies, 2PP produces
3D structures within the volume of the sample, without the necessity to deposit the material layer-bylayer.
Being an optical technology 2PP is also well compatible with microfluidic chips. We have used this
capacity of 2PP to produce 3D hydrogel structures directly within the microfluidic channels. The
photosensitive hydrogel formulation based on gelatin and the cells were delivered by perfusing the
channels, therefore enabling use of already assembled microfluidic chips. The latter aspects implies that
different materials, construct geometries and cell types can be tested with the same set of microfluidic chips
without changing their initial design or fabrication process.
By producing 3D traps, we were able to position the cells at the desired location within the microfluidic
channel. Porous 3D constructs, aligned to this cell position, are produced in the same step. Finally the
microfluidic chip is perfused with cell culture medium in order to remove the unpolymerized material and
for sustained cell culture. Our results demonstrate the general practicability of 2PP for producing complex
cell-containing 3D constructs within the microfluidic chips. This approach opens exciting perspectives
towards the precise engineering of 3D cell culture matrices for systematic studies of cell-cell and cellmaterial
interactions, and applications in organ-on-a-chip devices.

Two-photon polymerization (2PP) is a 3D printing approach based on femtosecond-laser- induced
polymerization. This technology allows one to produce complex CAD structures with remarkably high
spatial resolution. Furthermore, in contrast to other additive manufacturing technologies, 2PP produces
3D structures within the volume of the sample, without the necessity to deposit the material layer-bylayer.
Being an optical technology 2PP is also well compatible with microfluidic chips. We have used this
capacity of 2PP to produce 3D hydrogel structures directly within the microfluidic channels. The
photosensitive hydrogel formulation based on gelatin and the cells were delivered by perfusing the
channels, therefore enabling use of already assembled microfluidic chips. The latter aspects implies that
different materials, construct geometries and cell types can be tested with the same set of microfluidic chips
without changing their initial design or fabrication process.
By producing 3D traps, we were able to position the cells at the desired location within the microfluidic
channel. Porous 3D constructs, aligned to this cell position, are produced in the same step. Finally the
microfluidic chip is perfused with cell culture medium in order to remove the unpolymerized material and
for sustained cell culture. Our results demonstrate the general practicability of 2PP for producing complex
cell-containing 3D constructs within the microfluidic chips. This approach opens exciting perspectives
towards the precise engineering of 3D cell culture matrices for systematic studies of cell-cell and cellmaterial
interactions, and applications in organ-on-a-chip devices.

3D Printing, laser, bioprinting, hydrogel, microfluidic