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International Journal of Bioprinting Drop-on-demand laser bioprinting

Figure 1. Side-view representations of (A) conventional laser-induced side transfer (LIST) bioprinting and (B) the redesigned LIST incorporating
continuous capillary perfusion. (C) High-speed imaging captures the bioink ejection process. Scale bar: 200 μm.

2.9. Statistical analysis filled glass microcapillary (Figure 1A). The expansion
All results are reported as the mean and standard deviation of of the microbubble elevates the pressure within the
three independent experiments. We conducted a statistical microcapillary, leading to the ejection of micro-jets from
analysis using two-way Analysis of Variance (ANOVA) in its tip and the deposition of tiny droplets (Figure 1A).
GraphPad Prism 10 software (Figures 2, 3, 4B, and 5) and The redesigned LIST approach presented in this
one-way ANOVA (Figure 4C). The graphs were prepared work is outlined in Figure 2A. Similar to the original
using the same software. We employed the Comparison of design, droplet ejection is accomplished using focused ns
Coefficients of Variation Calculator in MedCalc Software laser pulses. However, in this modified approach, ink is
to generate Figure S1 (Supplementary File).
continually perfused through a glass capillary with a 200-
μm laser-machined hole in its side wall, functioning as a
3. Results and discussion nozzle. Surface tension prevents leakage in the absence of
3.1. Laser-induced side transfer using a laser pulses. This design offers separate control of the bioink
continuously perfused capillary flow rate inside the capillary from the printing (i.e., drop
In the initial implementation, LIST 23-26 utilizes low- ejection) rate, leading to four significant advancements
energy ns laser pulses (532 nm) in the range of 50 to compared to the initial design: (i) elimination of the need
150 μJ to create a microbubble near the tip of a bioink- to actively compensate for liquid lost via droplet ejection;

Volume 10 Issue 3 (2024) 511 doi: 10.36922/ijb.2832