Page 442 - IJB-10-5

International Journal of Bioprinting Bioprinting for large-sized tissue delivery

Figure 2. Development and characterization of the GP hydrogel. (A) Coupling optimization of exposure time and photoinitiator concentration (n = 4
for each condition). (B) Macroscopic (top row) and microscopic images (bottom row) of GelMA cylinders during mechanical stability evaluation, with
dotted lines indicating the sample edges. (C) Optimization of GP exposure time with different material compositions under 12.5% final concentration and
4× EY (n = 4 for each condition). (D) Cyclic compression tests with increasing strain from 10% to 80% (left) and corresponding hysteresis curves (right)
of 10G2.5P at 12.5 min light exposure. (E) Fatigue life cycles of different groups (n = 3). (F and G) Typical hysteresis curves of fatigue tests on GelMA
(F) and 10G2.5P (G) at 10 min light exposure under the EY system, with 80% strain for each compression cycle. (H) Comparison of this work (red star)
with previous reports on GelMA (green dots) and GP mixture (blue dots). (I) Schematic illustration of white light-induced reinforcement mechanism. (J)
Low-magnification SEM image of photocrosslinked GP hydrogel (left) and a high-magnification image corresponding to the rectangular region (right).
Magnification: 200,000× (J, left), 500,000× (J, right). Scale bars: 2 mm (B, top row); 100 μm (B, bottom row; J, left); 50 μm (J, right). Abbreviations: GelMA:
Gelatin methacryloyl; PEGDA: Poly(ethylene glycol) diacrylate; GP: Gelatin methacryloyl/poly(ethylene glycol) diacrylate; and EY: Eosin-Y.

Volume 10 Issue 5 (2024) 434 doi: 10.36922/ijb.3898