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CNC-enhanced Hydrogels for 3D Bioprinting
temperature. The enhancement effect was proportional to
CNC concentration within certain range. The printed 3D
construct of CNC-enhanced copolymer formed hydrogels
have strong mechanical properties to maintain the shape
with high resolution and precision. These results proved
that for the amorphous hydrogels, the printability of
materials can be improved by adding rigid nanocrystals
such as CNC. This method provides an effective approach
of enhancing the comprehensive performance of materials
for 3D bioprinting and other additive manufacturing
technologies.
Acknowledgments

This work was financially supported by the National Key
R&D Program of China (2017YFC1103400)..
Figure 8. Cell viability of fibroblasts in the culture media after
addition of PCA at given concentrations as a function of days. Conflicts of interest
2
The blank control with only culture medium each day was set as
100%. n=3. All authors declare that they have no conflict of interest.
Author contributions
of copolymer concentration. In the following 2 days, Y. C. designed the experiments. Y. C., R. J., Y. Z., M.
there was no significant difference between the additional Y. and Y. Z. performed the experiments and analyzed the
PCA of three different concentrations and blank control, results. Y. C. wrote the manuscript. L. W. supervised the
2
showing around 100% cell viability. Meanwhile, the co- work and revised themanuscript.
cultivation of hydrogel (20 wt% PCA +4.4 wt% CNC)
2
with fibroblasts, which were seeded on the surface of the References
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120 International Journal of Bioprinting (2021)–Volume 7, Issue 4