Coaxial Scale‐Up Printing of Diameter‐Tunable Biohybrid Hydrogel Microtubes with High Strength, Perfusability, and Endothelialization

Abstract

Although great progress has been made in coaxial extrusion printing toward generating microtubes for mimicking tubular tissues, these microtubes with insufficient mechanical properties and uncontrollable inherent swelling attribute severely hinder their utilization as load-bearing tubular tissue. Herein, a high-strength microtube is constructed by coaxial printing with a customized biohybird hydrogel ink consisting of nanoclay, H-bonding mono mer N-acryloyl glycinamide, and gelatin methacryloyl. The physical interpenetration between nanoclay and polymer chains endows this ink with excellent printability and structural stability, thus facilitating the precise deposition of scalable microtubes with tunable small-diameters and large-scale lengths. After photocrosslinking, 3D-printed biohybrid hydrogel microtube demonstrates marvelous mechanical properties with a tensile strength (≈22 MPa), a stretchability (≈500%), a Young's modulus (≈21 MPa), an anti-fatigue performance (≈200 cycles), a burst pressure (≈2500 mmHg), and a suture retention strength (≈280 gf) in swelling equilibrium state, which are far superior to the previously printed microtubes and generally satisfy the requirements of tubular tissues. Additionally, this obtained microtube also displays favorable biological features that support adhesion, spreading, and endothelialization of human umbilical vein endothelial cells. This study successfully develops a biohybrid hydrogel ink to fabricate a scalable high-strength microtube with enormous potential in regeneration of tube-like tissues.

Snake extract–laden hemostatic bioadhesive gel cross-linked by visible light

“…The peak at 3076 cm −1 of GelMA belongs to the stretching vibration of C═C─H (45). It can be seen that the methacrylate reaction did not change the basic chemical structure of gelatin (46). After visible light exposure, the peak at 3076 cm −1 almost disappeared, which is consistent with the 1 H NMR that the hydrogel has cross-linked through a free radical polymerization.…”

3D printing of tissue engineering scaffolds: a focus on vascular regeneration

“…carboxymethyl cellulose + 1.5% wt. cellulose nanofibers Physical crosslinking (ionic (CaCl 2 )) N/A Compositive material [ 113 ] Extrusion Biomaterial inks (nanoclay + GelMA + N-acryloyl glycinamide) 10% w/v nanoclay + 1%/9% (w/v) GelMA/N-acryloyl glycinamide Chemical crosslinking (UV) N/A Compositive material [ 114 ] Extrusion Bioinks excluding cells (semi-crosslinked alginate/CaCl 2 + platelet-rich plasma) 1%/0.025% (w/v) semi-crosslinked alginate/CaCl 2 + 50 U mL −1 platelet-rich plasma Physical crosslinking (ionic (CaCl 2 )) Human umbilical vein endothelial cells dECM-based compositive material [ 115 ] Inkjet Bioinks excluding cells (sodium alginate) 1% w/v sodium alginate Physical crosslinking (ionic (CaCl 2 )) NIH 3T3 mouse fibroblasts Natural material [ 116 , 117 ] Inkjet Biomaterial inks (sodium alginate) 0.8% w/v sodium alginate Physical crosslinking (ionic (CaCl 2 )) N/A Natural material [ 118 – 120 ] Inkjet Biomaterial inks (bacterial cellulose + polycaprolactone) bacterial cellulose blended with 10 wt.% polycaprolactone at 5:95 ratio Physical crosslinking (thermal crosslinking) N/A Compositive material [ 121 ] …”

Review on the Vascularization of Organoids and Organoids-on-a-Chip

“…Vascular-like structures include trachea, gastrointestinal tract, renal tubule and urinary catheter, which are distributed all over the body and the diameter of the tube ranges from micron to centimeter ( Kang et al, 2020 ). The mechanical strength of micro-tubules constructed by coaxial printing can be improved, through the construction of a new type of mixed high-strength hydrogel 3D printing ink ( Liang et al, 2020 ). The construction of the entire vascular network including macro-vessels and capillaries is based on the hydrogel and the secondary cross-linking encapsulation method of hydrogel has been proposed according to the cross-linking characteristics of the hydrogel.…”