Page 437 - IJB-9-2

International Journal of Bioprinting Shear-thinning and bioprinting parameters

CaCl were characterized rheologically and simulated, the Acknowledgments
2
following conclusions were drawn:
We want to thank the European Regional Development
Alginate-based hydrogels with cross-linking agent, Fund (ERDF) under the Interreg V A Spain – Portugal
consisting of 3.5%, 4.0%, and 5.0% (w/v) of alginate and (POCTEP) 2014-2020 program, project number 0633_
3.5% (w/v) of CaCl , show behavior typical of a non- BIOIMPACE_4_A.
2
Newtonian, shear-thinning fluid. Furthermore, the
viscosity and density increase with increasing alginate Funding
proportion.
This research was financially supported by the European
These hydrogels present a flow consistency index, k, that Regional Development Fund (ERDF) within the framework
increases with the alginate proportion, and a flow behavior of the Interreg VA Spain – Portugal (POCTEP) 2014-2020
index, n, that decreases. Thus, the lower the proportion of program, project number 0633_BIOIMPACE_4_A.
alginate, the closer the behavior index, n, to unity, that is,
the more it corresponds to Newtonian fluid behavior. Conflict of interest
Correct bioprinting requires an optimal extrusion The authors declare no conflicts of interest
pressure to be found. On the one hand, hydrogels extruded
at a low pressure give rise to droplets that are released later. Author contributions
On the other hand, if the extrusion pressure is excessive, Raúl Sánchez Sánchez: Investigation, Writing-original
the speed at which the fluid comes out is so high that it draft
produces splashes when it is deposited onto the plate. Jesús Manuel Rodríguez Rego: Investigation, Methodology,
Likewise, hydrogels with lower proportions of alginate review & editing
present higher sensitivity to the pressure applied at the Antonio Macías García: Funding acquisition, Project
inlet so that when the pressure is increased in smaller administration, Suppervision
ranges, they present greater variation in the extrusion flow, Laura Mendoza Cerezo: review & editing
unlike the case with higher alginate percentage samples. Antonio Díaz Parralejo: Writing-original draft, review &
Biomaterials with lower alginate percentages need editing, Supervision.
higher bioprinting pressures to achieve uniform flow. With Ethics approval and consent to participate
this, the extrusion times, which are directly related to the
head displacement speed needed to achieve a certain line Not applicable.
thickness, are shorter than those of hydrogels with higher
alginate percentage. Consent for publication
It has been verified that there is a clear linear Not applicable.
relationship between the pressure that must be applied
to the biomaterial at the inlet of the system and the flow Availability of data
consistency index rheological parameter, k. Likewise, Not applicable.
there is also a linear relationship between the extrusion
time, related in turn to the dispensing head displacement References
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Volume 9 Issue 2 (2023) 429 https://doi.org/10.18063/ijb.687