@article{HaiderAhmadYangetal.2021, author = {Haider, Malik Salman and Ahmad, Taufiq and Yang, Mengshi and Hu, Chen and Hahn, Lukas and Stahlhut, Philipp and Groll, J{\"u}rgen and Luxenhofer, Robert}, title = {Tuning the thermogelation and rheology of poly(2-oxazoline)/poly(2-oxazine)s based thermosensitive hydrogels for 3D bioprinting}, series = {Gels}, volume = {7}, journal = {Gels}, number = {3}, issn = {2310-2861}, doi = {10.3390/gels7030078}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-241781}, year = {2021}, abstract = {As one kind of "smart" material, thermogelling polymers find applications in biofabrication, drug delivery and regenerative medicine. In this work, we report a thermosensitive poly(2-oxazoline)/poly(2-oxazine) based diblock copolymer comprising thermosensitive/moderately hydrophobic poly(2-N-propyl-2-oxazine) (pPrOzi) and thermosensitive/moderately hydrophilic poly(2-ethyl-2-oxazoline) (pEtOx). Hydrogels were only formed when block length exceeded certain length (≈100 repeat units). The tube inversion and rheological tests showed that the material has then a reversible sol-gel transition above 25 wt.\% concentration. Rheological tests further revealed a gel strength around 3 kPa, high shear thinning property and rapid shear recovery after stress, which are highly desirable properties for extrusion based three-dimensional (3D) (bio) printing. Attributed to the rheology profile, well resolved printability and high stackability (with added laponite) was also possible. (Cryo) scanning electron microscopy exhibited a highly porous, interconnected, 3D network. The sol-state at lower temperatures (in ice bath) facilitated the homogeneous distribution of (fluorescently labelled) human adipose derived stem cells (hADSCs) in the hydrogel matrix. Post-printing live/dead assays revealed that the hADSCs encapsulated within the hydrogel remained viable (≈97\%). This thermoreversible and (bio) printable hydrogel demonstrated promising properties for use in tissue engineering applications.}, language = {en} }