Improving Fibrin Hydrogels’ Mechanical Properties, through Addition of Silica or Chitosan-Silica Materials, for Potential Application as Wound Dressings

Abstract

Fibrin is a protein-based hydrogel formed during blood coagulation. It can also be produced in vitro from human blood plasma, and it is capable of resisting high deformations. However, after each deformation process, it loses high amounts of water, which subsequently makes it mechanically unstable and, finally, difficult to manipulate. The objective of this work was to overcome the in vitro fibrin mechanical instability. The strategy consists of adding silica or chitosan-silica materials and comparing how the different materials electrokinetic-surface properties affect the achieved improvement. The siliceous materials electrostatic and steric stabilization mechanisms, together with plasma protein adsorption on their surfaces, were corroborated by DLS and ζ-potential measurements before fibrin gelling. These properties avoid phase separation, favoring homogeneous incorporation of the solid into the forming fibrin network. Young’s modulus of modified fibrin hydrogels was evaluated by AFM to quantitatively measure stiffness. It increased 2.5 times with the addition of 4 mg/mL silica. A similar improvement was achieved with only 0.7 mg/mL chitosan-silica, which highlighted the contribution of hydrophilic chitosan chains to fibrinogen crosslinking. Moreover, these chains avoided the fibroblast growth inhibition onto modified fibrin hydrogels 3D culture observed with silica. In conclusion, 0.7 mg/mL chitosan-silica improved the mechanical stability of fibrin hydrogels with low risks of cytotoxicity. This easy-to-manipulate modified fibrin hydrogel makes it suitable as a wound dressing biomaterial.

Usefulness of a Nanostructured Fibrin-Agarose Bone Substitute in a Model of Severely Critical Mandible Bone Defect

“…Application of nanostructuration methods allowed us to generate three-dimensional cylinder-type structures that were used to repair the mandible defects generated in an animal model. Although the biomechanical properties of these bioartificial structures were lower than those of mineralized bone [29], we found that the biomechanical behavior of our tissue substitutes was high compared to previously reported values for fibrin-based hydrogels [30]. Most likely, application of the biofabrication methods described in the present work-including nanostructuration and modification of the three-dimensional structure of the biomaterial to generate a rod-shaped cylinder-was able to improve the biomechanical properties of this type of biomaterial, as previously suggested [31].…”

Cardiac Tissue-like 3D Microenvironment Enhances Route towards Human Fibroblast Direct Reprogramming into Induced Cardiomyocytes by microRNAs

“…Both compositions showed a gel-like behavior with the storage modulus (G’) higher than the loss modulus (G’’) for the range of frequencies investigated. The elastic modulus at 1 Hz ( Figure 3 d) was obtained from the storage modulus as described in the materials and methods section, assuming a Poisson’s ratio of 0.5 [ 23 , 24 ]. Three-dimensional hydrogels showed an average elastic modulus of 64 ± 7 Pa, while an average value of 23 ± 1 Pa was obtained for 3D BM hydrogel samples.…”

Inactivation of human plasma alters the structure and biomechanical properties of engineered tissues

“…Our group has explored the addition of biomaterials like genipin, which used in concentrations of 0.1%–0.5%, improved structural and biomechanical properties of NFAH ( Campos et al, 2018 ). A different approach could be the addition of 0.7 mg/ml chitosan-silica which has been shown to improve the mechanical stability of fibrin hydrogels with low risks of cytotoxicity ( Becerra et al, 2021 ). Nevertheless, “ in vivo ” studies are still needed to check efficacy and security of either option.…”