Sonochemical Degradation Of Gelatin Methacryloyl To Control Viscoelasticity for Inkjet Bioprinting.

Inkjet printing enables the mimicry of the microenvironment of natural complex tissues by patterning cells and hydrogels at a high resolution. However, the polymer content of an inkjet-printable bioink is limited as it leads to strong viscoelasticity in the inkjet nozzle. Here we demonstrate that sonochemical treatment controls the viscoelasticity of a gelatin methacryloyl-based bioink by shortening the length of polymer chains without causing chemical destruction of the methacryloyl groups. The rheological properties of treated GelMA inks were evaluated by a piezo-axial vibrator over a wide range of frequencies between 10 and 10000 Hz. This approach enables us to effectively increase the maximum printable polymer concentration from 3% to 10%. We then studied how the sonochemical treatment effectively controls the microstructure and mechanical properties of GelMA hydrogel constructs after crosslinking while maintaining its fluid properties within the printable range. The conrol of mechanical properties of GelMA hydrogels could lead fibroblasts more spreading on the hydrogels and fabricate three-dimensional cell-laden multilayered hydrogel constructs containing layers with different physical properties by using high-resolution inkjet printing. The sonochemical treatment will deliver a new path to inkjet bioprinting to build microarchitectures with various physical properties by expanding the range of applicable bioinks. This article is protected by copyright. All rights reserved.