Can hydrogel micropatterns be used for tissue engineering with photocrosslinking polymers?

Several research groups have previously reported hydrogel micropatterning for tissue engineering with photocrosslinking polymers, including derivatives of poly(ethylene glycol) (PEG) polysaccharides and proteins (e.g., gelatin) .

Do hydrogel polymer chains need to be cross-linked?

In order to create stable cell culture scaffolds the hydrogel polymer chains need to be cross-linked to prevent degradation. The selection of cross-linking strategy is determined by the application of the biomaterial. If cells shall be encapsulated in the hydrogel for 3D cultures, the cross-linking chemistry must not be toxic to the cells.

Are peg based hydrogels a good choice?

When using a hydrogel for forming a device geometry rather than a cell scaffold that the cells should be able to penetrate, PEG based hydrogels is a specifically good choice as it prevents protein adsorption and does not support cell adherence ( Koh et al., 2003; Zhu, 2010 ).

How is a hydrogel layer formed in a microchannel?

Parts of this solution is then removed by perfusing cell media centrally in the microchannel, resulting in a hydrogel layer on the channel walls with a circular opening in the centre ( Bischel et al., 2012 ). The technique offers good reproducibility with a hydrogel layer thickness of around 700 μm.

How do patterned hydrogel cell culture scaffolds interact with the extracellular matrix?

Cells interact with their surrounding environment, the extracellular matrix, via mechanical and chemical cues. The reports so far on patterned hydrogel cell culture scaffolds are limited and to date it is mostly chemical modifications of the biomaterial that have been explored.

How do hydrogels control surface chemistry?

Chemical patterning of hydrogels to control surface chemistry at the micrometre level permits mimicking native tissue architecture. By patterning biochemical cues on the surface one can spatially control cell adhesion, Fig. 9.