Development, characterization, and in vitro evaluation of TEMPO-oxidized microcellulose-based biomaterial inks for three-dimensional bioprinting

Abstract

Three-dimensional (3D)-bioprinting is widely used in tissue engineering due to its customizability, avoidance of allogeneic rejection, and absence of disease transmission risk. Cellulose, a renewable natural polymer, is valued as an excellent bioink for its non-toxicity, biocompatibility, biodegradability, and cost-effectiveness. In this study, 2,2,6,6-tetramethylpiperidine-1-oxyl radical-oxidized microcellulose was subjected to homogenization. The resulting bioink was characterized using Fourier transform infrared spectroscopy, conductivity measurements, and rheometric analyses. Scaffolds were subsequently fabricated using 3D bioprinting, and cell viability was evaluated through cell culture on the printed scaffold. Optimization of the oxidation process revealed that a 6-h treatment achieved the highest degree of oxidation, exhibiting superior viscosity and printability compared to other durations. A straightforward scale-up of the 6-h process enabled the successful fabrication of 3D-bioprinted scaffolds. Cell culture experiments demonstrated excellent cell adhesion and viability on the scaffolds. Our findings demonstrate that oxidized microcellulose serves as a promising bio-based, non-toxic, structurally stable, and cell-compatible bioink for 3D bioprinting in tissue engineering applications.

Keywords

Cellulose / Cell viability / Three-dimensional bioprinting / Tissue engineering

Funding

This research was funded by the China Scholarship Council, grant number 202208330024.

Conflict of interest

Cedric Delattre serves as an Editorial Board Member of the journal but had no involvement, directly or indirectly, in the editorial or peer-review process for this manuscript. The other authors declare that they have no competing interests.

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