Dextran‐based hydrogel with enhanced mechanical performance via covalent and non‐covalent cross‐linking units carrying adipose‐derived stem cells toward vascularized bone tissue engineering

Abstract

Hydrogels for biomedical applications were limited toward bone tissue engineering due to the poor mechanical performance. Tough hydrogels with strong and elastic features have received extensive attention, the application of which, however, was limited by their degradation. The present study introduced an approach to enhance mechanical properties of hydrogel while ensuring its degradation. Carboxyl dextran (Dex) was grafting modified by poly (ε‐caprolactone) (PCL), sequentially followed by being cross‐linked through polyethyleneglycol 400 (PEG400) to yield a gel with covalent cross‐linking units in DMSO. The gel was underwent solvent displacement in H2O to induce hydrophobic association of PCL to form non‐covalent cross‐linking units. The tough Dex‐g‐PCL hydrogel showed maximum strain of Dex‐g‐PCL hydrogel was 90% ± 6%, with the corresponding stress of 2.7 ± 0.2 MPa, which was significantly enhanced when comparing to dextran hydrogel (maximum strain 65% ± 5%, with the corresponding stress of 0.225 ± 0.06 MPa). Most hydrogel degraded after 12 w in vivo with only a little residues. Adipose‐derived stem cells (ASCs) proliferated well after being seeded in hydrogel to form micro‐mass at 14 days post‐seeding. In vitro and in vivo angiogenesis, as well as in vitro osteogenesis illustrated the potential of the Dex‐g‐PCL hydrogel carrying ASCs toward vascularized bone tissue engineering. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1120–1131, 2019.

A V(iii)-induced metallogel with solvent stimuli-responsive properties: structural proof-of-concept with MD simulations

“…In accordance with previous research studies, throughout the gelation process, mechanical properties such as the rigidity of metallogels and hydrogels are increased due to gelation. [75][76][77][78] The enhanced shear strength of the MG3 metallogel reinforces the assumption that this structure is likely to be more resistant to deformation. This assumption can be assessed in subsequent computational studies by calculating the viscosity of the metallogel networks.…”

“…7 the required shear stress for deformation of simulated networks was different for each case, deviated from each other aer 15 ns, and increased from MG1 to MG3 through the gel formation. [75][76][77][78][79] This indicates an increase in the shear strength of the Vgel in the MG3 system, in which the gel components has a more robust self-assembly. Increasing the DMF/H 2 O solvent ratio in the system leads to more ordered structure that ultimately increases the integrity of the gel.…”

Microbial exopolysaccharides in the biomedical and pharmaceutical industries

“…The poor mechanical performance of hydrogels has limited their use in biological applications to bone tissue engineering. The application of tough hydrogels with strong and elastic properties has garnered a lot of interest, but this has been constrained by their deterioration [ 48 ].…”

Removal and recovery of nutrients and value-added products from wastewater: technological options and practical perspective

“…It has also shown to improve food packaging [156,157] 1.0% chitosan Used for base coating and maintaining the safety and quality of fresh bell peppers, stored at room temperature for 21 days [158] Dextran-based hydrogels Physical strength: maximum strain (90%) and corresponding stress of 2.7 MPa. Adipose-derived stem cells (ASCs) were proliferated and seeded in hydrogel to form micro-mass after14 days of post-seeding [159] Dextran-based polymers and scaffolds Used for controlled drug release and tissue engineering [160] Lignin-mediated green synthesis of AgNPs in carrageenan matrix Used for wound dressing applications and it has shown to reduce the wound area to < 3% within 2 weeks of application. This film also exhibited strong antibacterial activity against S. aureus and E. coli [161] κ-carrageenan aerogels prepared using different dissolution media (optimum at pH 7.4)…”