TY  - JOUR
A1  - Hazur, Jonas
A1  - Detsch, Rainer
A1  - Karakaya, Emine
A1  - Kaschta, Joachim
A1  - Teßmar, Jörg
A1  - Schneidereit, Dominik
A1  - Friedrich, Oliver
A1  - Schubert, Dirk W
A1  - Boccaccini, Aldo R
T1  - Improving alginate printability for biofabrication: establishment of a universal and homogeneous pre-crosslinking technique
JF  - Biofabrication
N2  - Many different biofabrication approaches as well as a variety of bioinks have been developed by researchers working in the field of tissue engineering. A main challenge for bioinks often remains the difficulty to achieve shape fidelity after printing. In order to overcome this issue, a homogeneous pre-crosslinking technique, which is universally applicable to all alginate-based materials, was developed. In this study, the Young’s Modulus after post-crosslinking of selected hydrogels, as well as the chemical characterization of alginate in terms of M/G ratio and molecular weight, were determined. With our technique it was possible to markedly enhance the printability of a 2% (w/v) alginate solution, without using a higher polymer content, fillers or support structures. 3D porous scaffolds with a height of around 5 mm were printed. Furthermore, the rheological behavior of different pre-crosslinking degrees was studied. Shear forces on cells as well as the flow profile of the bioink inside the printing nozzle during the process were estimated. A high cell viability of printed NIH/3T3 cells embedded in the novel bioink of more than 85% over a time period of two weeks could be observed.
KW  - alginate
KW  - bioprinting
KW  - rheology
KW  - bioink
KW  - pre-crosslinking
KW  - printability
KW  - shape fidelity
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-254030
VL  - 12
IS  - 4
ER  - 
TY  - JOUR
A1  - Hu, Chen
A1  - Hahn, Lukas
A1  - Yang, Mengshi
A1  - Altmann, Alexander
A1  - Stahlhut, Philipp
A1  - Groll, Jürgen
A1  - Luxenhofer, Robert
T1  - Improving printability of a thermoresponsive hydrogel biomaterial ink by nanoclay addition
JF  - Journal of Materials Science
N2  - As a promising biofabrication technology, extrusion-based bioprinting has gained significant attention in the last decade and major advances have been made in the development of bioinks. However, suitable synthetic and stimuli-responsive bioinks are underrepresented in this context. In this work, we described a hybrid system of nanoclay Laponite XLG and thermoresponsive block copolymer poly(2-methyl-2-oxazoline)-b-poly(2-n-propyl-2-oxazine) (PMeOx-b-PnPrOzi) as a novel biomaterial ink and discussed its critical properties relevant for extrusion-based bioprinting, including viscoelastic properties and printability. The hybrid hydrogel retains the thermogelling properties but is strengthened by the added clay (over 5 kPa of storage modulus and 240 Pa of yield stress). Importantly, the shear-thinning character is further enhanced, which, in combination with very rapid viscosity recovery (~ 1 s) and structure recovery (~ 10 s), is highly beneficial for extrusion-based 3D printing. Accordingly, various 3D patterns could be printed with markedly enhanced resolution and shape fidelity compared to the biomaterial ink without added clay.
KW  - printability
KW  - thermoresponsive hydrogel
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234894
SN  - 0022-2461
VL  - 56
ER  -