A Guide to Polysaccharide-Based Hydrogel Bioinks for 3D Bioprinting Applications

Abstract

Three-dimensional (3D) bioprinting is an innovative technology in the biomedical field, allowing the fabrication of living constructs through an approach of layer-by-layer deposition of cell-laden inks, the so-called bioinks. An ideal bioink should possess proper mechanical, rheological, chemical, and biological characteristics to ensure high cell viability and the production of tissue constructs with dimensional stability and shape fidelity. Among the several types of bioinks, hydrogels are extremely appealing as they have many similarities with the extracellular matrix, providing a highly hydrated environment for cell proliferation and tunability in terms of mechanical and rheological properties. Hydrogels derived from natural polymers, and polysaccharides, in particular, are an excellent platform to mimic the extracellular matrix, given their low cytotoxicity, high hydrophilicity, and diversity of structures. In fact, polysaccharide-based hydrogels are trendy materials for 3D bioprinting since they are abundant and combine adequate physicochemical and biomimetic features for the development of novel bioinks. Thus, this review portrays the most relevant advances in polysaccharide-based hydrogel bioinks for 3D bioprinting, focusing on the last five years, with emphasis on their properties, advantages, and limitations, considering polysaccharide families classified according to their source, namely from seaweed, higher plants, microbial, and animal (particularly crustaceans) origin.

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

“…Hydrogels can be produced with both natural (e.g., cellulose, chitin, alginate, pectin, starch, collagen and fibrin), and synthetic (e.g., polyacrylamide, poly(vinyl alcohol) and poly(2-hydroxyethyl methacrylate)) derived polymers [18,19]. The use of biopolymeric hydrogels, based on polysaccharides or proteins, for 3D bioprinting applications offers several advantages over the synthetic ones [20,21]. Specifically, in addition to their biocompatibility towards mammalian cells and tissues, most biopolymers are biodegraded under physiological conditions, leading to the formation of nontoxic degradation products.…”

“…Amid the vast array of polysaccharides, alginate is a polyanionic water-soluble linear polysaccharide extracted from brown algae [23] that forms hydrogels under mild conditions, and almost instantaneously, by ionotropic gelation with divalent cations, such as Ca 2+ [24]. Actually, alginate hydrogels are one of the most studied biomaterials in the domain of 3D bioprinting [21,25,26], because of their excellent tunability (in terms of viscosity modulation, for instance, by varying the concentration of the biopolymer) and printability (in terms of shear-thinning properties) [24]. Albeit their widely recognized and explored advantages, alginate hydrogels are also known to have some limitations.…”

Introductory Chapter: Hydrogels in Comprehensive Overviews, Recent Trends on Their Broad Applications

“…An adequate bioink for use in 3D bioprinting needs to satisfy certain conditions, such as bioactivity, cytocompatibility, and printability [29]. Regarding the polymers that make up the hydrogel structure, polysaccharides are extensively used to produce bioinks, such as cellulose, hyaluronic acid, alginate, pectin, chitosan, carrageenan, or agarose [30]. 3D bioprinted hydrogels have a large use for tissue bioprinting, including skin, muscles, bones, cartilages, neurons, cardiac fibers, and blood veins [31].…”

Advances in 3D Gel Printing for Enzyme Immobilization

“…With more research, materials and methods developed in these areas can be translated to immobilizing cell-free enzymes. For example, many polysaccharide-based hydrogel materials, such as hyaluronic acid, pectin, and various cellulose derivatives, which have already been widely used for drug delivery [ 98 ] and tissue engineering [ 99 , 100 ] could be applied to cell-free systems. In particular, many bacterial polysaccharides have been shown recently to exhibit antibiofilm activity [ 101 ] and the possibility of utilizing this bioactivity in 3D printed immobilized enzyme seems extremely promising for preventing biofouling and improving enzyme longevity.…”