Improving alginate printability for biofabrication: establishment of a universal and homogeneous pre-crosslinking technique

Biofabrication. 2020 Jul 9;12(4):045004. doi: 10.1088/1758-5090/ab98e5.

Abstract

Many different biofabrication approaches as well as a variety of bioinks have been developed by researchers working in the field of tissue engineering. A main challenge for bioinks often remains the difficulty to achieve shape fidelity after printing. In order to overcome this issue, a homogeneous pre-crosslinking technique, which is universally applicable to all alginate-based materials, was developed. In this study, the Young's Modulus after post-crosslinking of selected hydrogels, as well as the chemical characterization of alginate in terms of M/G ratio and molecular weight, were determined. With our technique it was possible to markedly enhance the printability of a 2% (w/v) alginate solution, without using a higher polymer content, fillers or support structures. 3D porous scaffolds with a height of around 5 mm were printed. Furthermore, the rheological behavior of different pre-crosslinking degrees was studied. Shear forces on cells as well as the flow profile of the bioink inside the printing nozzle during the process were estimated. A high cell viability of printed NIH/3T3 cells embedded in the novel bioink of more than 85% over a time period of two weeks could be observed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alginates / chemistry*
  • Animals
  • Bioprinting*
  • Cell Shape
  • Cell Survival
  • Cross-Linking Reagents / chemistry*
  • Elastic Modulus
  • Mice
  • NIH 3T3 Cells
  • Rheology
  • Stress, Mechanical
  • Time Factors
  • Viscosity

Substances

  • Alginates
  • Cross-Linking Reagents