Among various available 3D bioprinting techniques, extrusion-based three-dimensional (3D) bio-printing allows the deposition of cell-laden bio-ink, ensuring predefined scaffold architecture that may offer living tissue regeneration. With a combination of unique characteristics such as biocompatibility, less cell toxicity, and high-water content, natural hydrogels are a great candidate for bio-ink formulation for the extrusion-based 3D bioprinting process. However, due to its low mechanical integrity, hydrogel faces a common challenge in maintaining structural ty. To tackle this challenge, we characterized the rheological properties of a set of hybrid hydrogels composed of cellulose-derived nanofiber (TEMPO-mediated nano-fibrillated cellulose, TONFC), carboxymethyl cellulose (CMC) and commonly used alginate. A total of 46 compositions were prepared using higher (0.5% and 1.0%) and lower percentages (0.005% and 0.01%) of TONFC, 1%–4% of CMC, and 1%–4% of alginate to analyze the rheological properties. The shear thinning coefficients of n and K were determined for each composition from the flow diagram and co-related with the 3D printability. The ability to control rheological properties with various ratios of a nanofiber can help achieve a 3D bio-printed scaffold with defined scaffold architecture.
This content will become publicly available on May 21, 2024
Influence of Short Fiber Encapsulated in Hybrid Hydrogel For 3d Bioprinting Process: Aspect of Rheological Properties
Extrusion-based three-dimensional (3D) bio-printing is one of the several 3D bioprinting methods that is frequently
used in current times. This method enables the accurate deposition of cell-laden bio-ink while ensuring a
predetermined scaffold architecture that may allow living tissue regeneration. Natural hydrogels are a strong choice
for bio-ink formulation for the extrusion-based 3D bioprinting method because they have a combination of unique
properties, which include biocompatibility, reduced cell toxicity, and high-water content. However, due to its low
mechanical integrity, hydrogel frequently struggles to retain structural stability. To overcome this challenge, we
evaluated the rheological characteristics of distinct hybrid hydrogels composed of carboxymethyl cellulose (CMC), a
widely used alginate, and nanofibers generated from cellulose (TEMPO-mediated nano-fibrillated cellulose, TONFC).
Therefore, to examine the rheological properties, a set of compositions was developed incorporating CMC (1%–4%),
alginate (1%–4%), and higher and lower contents of TONFC (0.5%) and (0.005%) respectively. From the flow
diagram, the shear thinning coefficients of n and K were calculated, which were later linked to the 3D printability.
With the guidance of diverse nanofiber ratios, it is possible to regulate the rheological properties and create 3D bioprinted scaffolds with well-defined scaffold architecture.
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- Award ID(s):
- 1757371
- NSF-PAR ID:
- 10486633
- Editor(s):
- Babski-Reeves, K; Eksioglu, B; Hampton, D.
- Publisher / Repository:
- Institute of Industrial and Systems Engineers
- Date Published:
- Journal Name:
- Proceedings of the IISE Annual Conference & Expo 2023
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Among various available 3D bioprinting techniques, extrusion-based three-dimensional (3D) bioprinting allows the deposition of cell-laden bioink, ensuring predefined scaffold architecture that may offer living tissue regeneration. With a combination of unique characteristics such as biocompatibility, less cell toxicity, and high water content, natural hydrogels are a great candidate for bioink formulation for the extrusion-based 3D bioprinting process. However, due to its low mechanical integrity, hydrogel faces a common challenge in maintaining structural integrity. To tackle this challenge, the rheological properties, specifically the shear thinning behavior (reduction of viscosity with increasing the applied load/shear rate on hydrogels) of a set of hybrid hydrogels composed of cellulose-derived nanofiber (TEMPO-mediated nano-fibrillated cellulose, TO-NFC), carboxymethyl cellulose (CMC), and commonly used alginate, were explored. A total of 46 compositions were prepared using higher (0.5% and 1.0%) and lower percentages (0.005% and 0.01%) of TO-NFC, 1–4% of CMC, and 1–4% of alginate to analyze the shear thinning factors such as the values of n and K, which were determined for each composition from the flow diagram and co-related with the 3D printability. The ability to tune shear thinning factors with various ratios of a nanofiber can help achieve a 3D bio-printed scaffold with defined scaffold architecture.more » « less
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