3D Printable Dynamic Hydrogel: As Simple as it Gets!

Abstract

3D printing technology offers a vast range of applications for tissue engineering applications. Over the past decade a vast range of new equipment has been developed; while, 3D printable biomaterials, especially hydrogels, are investigated to fit the printability requirements. The current candidates for bioprinting often require post‐printing cross‐linking to maintain their shape. On the other hand, dynamic hydrogels are considered as the most promising candidate for this application with their extrudability and self‐healing properties. However, it proves to be very difficult to match the required rheological in a simple material. Here, this study presents for the first time the simplest formulation of a dynamic hydrogel based on thiol‐functionalized hyaluronic acid formulated with gold ions that fulfill all the requirements to be printed without the use of external stimuli, as judged by the rheological studies. The printability is also demonstrated with a 3D printer allowing for the printing of the dynamic hydrogel as it is, achieving 3D construct with a relatively good precision and up to 24 layers, corresponding to 10 mm high. This material is the simplest 3D printable hydrogel and its mixture with cells and biological compounds is expected to open a new era in 3D bioprinting.

Local and Sustained Baricitinib Delivery to the Skin through Injectable Hydrogels Containing Reversible Thioimidate Adducts

“…Specifically, thiolated hyaluronic acid formed from the amidation reaction between the carboxyl of hyaluronic acid to cysteamine with a degree of thiol modification of either 30% or 50% and a molecular weight of ≈100 kDa was used ( Figure A). [ 59 ] The thiols function to form thioimidates with baricitinib as well as disulfide crosslinks between polymer chains to form hydrogels (Figure 2B).…”

“…Materials: Thiolated hyaluronic acid was purchased from a supplier (HAworks, Bedminster, NJ), synthesized as previously described through an amidation reaction at the carboxyl of hyaluronic acid with 30% or 50% degree of modification of disaccharides. [59] Polymers were stored under vacuum in a desiccator at room temperature. All other chemical reagents were purchased from Sigma-Aldrich (St. Louis, MO) and stored according to manufacturer's instructions unless otherwise indicated.…”

3D printed scaffolds based on hyaluronic acid bioinks for tissue engineering: a review

“…License Number:5618161075332. F Thiol-functionalized hyaluronic acid dynamic hydrogel with Au ions for better printing accuracy and applicability [ 56 ]. Copyright 2022, Wiley–VCH GmbH.…”

“…Hydrazone and oxime formation reactions have also been employed, such as hydrazine crosslinking of HA hydrogels, in which carbodihydrazide is used as the hydrazine group and hyaluronic aldehyde is used as a substrate for recombinant human bone morphogenetic protein-2 [ 113 ]. Ion replacement reactions include HA dynamic hydrogels technology based on metal (e.g., Au) sulfate/disulfide exchange reactions [ 56 ]. Notably, the interaction between sulfhydryl groups and Au ions minimizes the oxidation of sulfhydryl groups to disulfides at physiological pH levels ( Fig.…”

Essential Guide to Hydrogel Rheology in Extrusion 3D Printing: How to Measure It and Why It Matters?

“…In this technique, 3D structures are built in a layer-by-layer mode, using sequential extrusion of materials from a nozzle, following a predesigned computer model [3,4]. In particular, extrusion-based 3D printing of hydrogels, namely cross-linked networks of flexible polymer chains containing a large amount of water as fill solvent, is a technology that is gaining popularity due to its potential applications in tissue engineering, drug delivery, and regenerative medicine [5][6][7][8]. Hydrogels are highly biocompatible materials that can mimic the properties of natural Gels 2023, 9, 517 2 of 21 tissues, and the fact that 3D printing allows for the creation of high-resolution customised structures with precise control over their size, shape, and mechanical properties is one reason why this technology is so widely used at present.…”