Natural Hydrogel-Based Bio-Inks for 3D Bioprinting in Tissue Engineering: A Review

Abstract

Three-dimensional (3D) printing is well acknowledged to constitute an important technology in tissue engineering, largely due to the increasing global demand for organ replacement and tissue regeneration. In 3D bioprinting, which is a step ahead of 3D biomaterial printing, the ink employed is impregnated with cells, without compromising ink printability. This allows for immediate scaffold cellularization and generation of complex structures. The use of cell-laden inks or bio-inks provides the opportunity for enhanced cell differentiation for organ fabrication and regeneration. Recognizing the importance of such bio-inks, the current study comprehensively explores the state of the art of the utilization of bio-inks based on natural polymers (biopolymers), such as cellulose, agarose, alginate, decellularized matrix, in 3D bioprinting. Discussions regarding progress in bioprinting, techniques and approaches employed in the bioprinting of natural polymers, and limitations and prospects concerning future trends in human-scale tissue and organ fabrication are also presented.

Alginate-Lysozyme Nanofibers Hydrogels with Improved Rheological Behavior, Printability and Biological Properties for 3D Bioprinting Applications

“…Hence, the basic aspects of an ideal bioink are mainly associated with biocompatibility and biodegradability, high mechanical integrity and stability, and the capability to foster cell adhesion and proliferation [6]. Among the different types of bioinks, the ones based on hydrogels are the most described and investigated materials [7,8], because their peculiar architecture provides permeability to oxygen, nutrients, and other watersoluble compounds, along with allowing cellular migration and communication within the porous flexible network [9]. Moreover, the selection of the bioprinting technique, for instance, between extrusion-based [10,11], material jetting [12,13], or Vat-polymerization methodologies [14,15], strongly depends on the type of bioink [16], with extrusion bioprinting being the most explored for hydrogels [17].…”

The Circular Economy Paradigm: Modification of Bagasse-Derived Lignin as a Precursor to Sustainable Hydrogel Production

“…Similarly, the literature highlights the potential of enhancing the solubility of lignin in organic solvents, via the conversion of hydrophilic hydroxyl groups to hydrophobic ester groups using acetylation reactions [12], thus making it a suitable candidate for the preparation of hydrogels [13]. Renewable hydrogel production is of interest in the present study due to its tissue engineering applications, which arise from its inherent matrices that can support cell proliferation [14,15].…”

A focused review on three-dimensional bioprinting technology for artificial organ fabrication

“…Furthermore, standardised bio-ink formulations that can be used in a variety of bioprinting applications are urgently needed. 74 This requires accurate modelling of final tissue structures.…”