2022/09/27 by Sebastian Müller, Müller, Sebastian Johannes, Ben Fabry +3
Biochemistry, Genetics and Molecular Biology · Engineering · #3D Printing in Biomedical Research #Biological Physics (physics.bio-ph) #Cell Image Analysis Techniques #FOS: Physical sciences #Microfluidic and Bio-sensing Technologies #Soft Condensed Matter (cond-mat.soft)
paper · pdf · doi:10.48550/arxiv.2209.13666
openalex publication_date 2022/09/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Bioprinting of living cells can cause major shape deformations, which may severely affect cell survival and functionality. While the shear stresses occurring during cell flow through the printer nozzle have been quantified to some extent, the extensional stresses occurring as cells leave the nozzle into the free printing strand have been mostly ignored. Here we use Lattice-Boltzmann simulations together with a finite-element based cell model to study cell deformation at the nozzle exit. Our simulation results are in good qualitative agreement with experimental microscopy images. We show that for cells flowing in the center of the nozzle extensional stresses can be significant, while for cells flowing off-center their deformation is dominated by the shear flow inside the nozzle. From the results of these simulations, we develop two simple methods that only require the printing parameters (nozzle diameter, flow rate, bioink rheology) to (i) accurately predict the maximum cell stress occurring during the 3D bioprinting process and (ii) approximately predict the cell strains caused by the elongational flow at the nozzle exit.