Experimental characterization and computational modeling of hydrogel cross-linking for bioprinting applications

authored by: Aidin Hajikhani, Franca Scocozza, Michele Conti, Michele Marino, Ferdinando Auricchio, Peter Wriggers
Abstract: Alginate-based hydrogels are extensively used to create bioinks for bioprinting, due to their biocompatibility, low toxicity, low costs, and slight gelling. Modeling of bioprinting process can boost experimental design reducing trial-and-error tests. To this aim, the cross-linking kinetics for the chemical gelation of sodium alginate hydrogels via calcium chloride diffusion is analyzed. Experimental measurements on the absorbed volume of calcium chloride in the hydrogel are obtained at different times. Moreover, a reaction-diffusion model is developed, accounting for the dependence of diffusive properties on the gelation degree. The coupled chemical system is solved using finite element discretizations which include the inhomogeneous evolution of hydrogel state in time and space. Experimental results are fitted within the proposed modeling framework, which is thereby calibrated and validated. Moreover, the importance of accounting for cross-linking-dependent diffusive properties is highlighted, showing that, if a constant diffusivity property is employed, the model does not properly capture the experimental evidence. Since the analyzed mechanisms highly affect the evolution of the front of the solidified gel in the final bioprinted structure, the present study is a step towards the development of reliable computational tools for the in silico optimization of protocols and post-printing treatments for bioprinting applications.
Organisation(s): Institute of Continuum Mechanics
External Organisation(s): University of Pavia
Type: Article
Journal: International Journal of Artificial Organs
Volume: 42
Pages: 548-557
No. of pages: 10
ISSN: 0391-3988
Publication date: 10.2019
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Bioengineering, Medicine (miscellaneous), Biomaterials, Biomedical Engineering
Electronic version(s): https://doi.org/10.1177/0391398819856024 (Access: Closed)
: Details in the research portal "Research@Leibniz University"

BibTeX

@article{5b9d5f8edfd648c5b1e96bbaa5ce9574,
title = "Experimental characterization and computational modeling of hydrogel cross-linking for bioprinting applications",
abstract = "Alginate-based hydrogels are extensively used to create bioinks for bioprinting, due to their biocompatibility, low toxicity, low costs, and slight gelling. Modeling of bioprinting process can boost experimental design reducing trial-and-error tests. To this aim, the cross-linking kinetics for the chemical gelation of sodium alginate hydrogels via calcium chloride diffusion is analyzed. Experimental measurements on the absorbed volume of calcium chloride in the hydrogel are obtained at different times. Moreover, a reaction-diffusion model is developed, accounting for the dependence of diffusive properties on the gelation degree. The coupled chemical system is solved using finite element discretizations which include the inhomogeneous evolution of hydrogel state in time and space. Experimental results are fitted within the proposed modeling framework, which is thereby calibrated and validated. Moreover, the importance of accounting for cross-linking-dependent diffusive properties is highlighted, showing that, if a constant diffusivity property is employed, the model does not properly capture the experimental evidence. Since the analyzed mechanisms highly affect the evolution of the front of the solidified gel in the final bioprinted structure, the present study is a step towards the development of reliable computational tools for the in silico optimization of protocols and post-printing treatments for bioprinting applications.",
keywords = "bioprinting, chemical cross-linking, diffusive properties, gelation, Sodium alginate",
author = "Aidin Hajikhani and Franca Scocozza and Michele Conti and Michele Marino and Ferdinando Auricchio and Peter Wriggers",
note = "Funding information: The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: A.H. and M.M. acknowledge that this work has been carried out within the framework of the SMART BIOTECS alliance between the Technical University of Braunschweig and the Leibniz University of Hannover. This initiative is financially supported by the Ministry of Science and Culture (MWK) of Lower Saxony, Germany. Moreover, F.A., M.C., and F.S. acknowledge the 3D@UniPV Project.",
year = "2019",
month = oct,
doi = "10.1177/0391398819856024",
language = "English",
volume = "42",
pages = "548--557",
journal = "International Journal of Artificial Organs",
issn = "0391-3988",
publisher = "Wichtig Publishing Srl",
number = "10",
}