Meshes‐to‐Fibrils Transition of Gellan Gum Hydrogel Architecture by Thermal Annealing

Abstract

The possibilities created by tuning the architecture of hydrogels open up extensive opportunities for their application in tissue engineering and biomedicine. A simple and effective procedure is developed here, based on thermal annealing, which affects the alignment of the fibrils and results in a mesh‐like structure. Atomic force microscopy and cryo‐scanning electron microscopy are used to characterize the resultant gel. The alignment angle is demonstrated to take place spontaneously, providing an easy way for self‐assembly of such structures. The protocol developed here is likely to be applicable in numerous areas of biomedicine and tissue engineering.

Nanofibrillar Hydrogels by Temperature Driven Self‐Assembly: New Structures for Cell Growth and Their Biological and Medical Implications

“…The solubility GG is between 30 and 35 mg mL −1 , as has been practically found out earlier. [ 87 ] The concentration of the solution we originally used was 10 mg mL −1 . This concentration is achieved between 8 and 10 h of the annealing procedure.…”

Robust Topographical Micro-Patterning of Nanofibrillar Collagen Gel by In Situ Photochemical Crosslinking-Assisted Collagen Embossing

“…The self-assembly process based on non-covalent molecular interactions, such as hydrophobic forces, electrostatic interactions, and hydrogen bonding, is one of the powerful methods to produce in vivo-like nanofibrils as a bottom–up approach [ 26 , 27 , 28 , 29 ]. The self-assembled nanofibrillar collagen constructs have been previously found to provide the best environment for cell culture; however, one of the major concerns with respect to the micro-patterning of the nanofibrillar collagen gel is the structural robustness of the resultant micro-patterns in aqueous media.…”

Strategies for Anisotropic Fibrillar Hydrogels: Design, Cell Alignment, and Applications in Tissue Engineering

“…(e) The distribution of hydrogel fibers in degrees. Reprinted with permission from ref . Copyright 2020 Wiley.…”

“…49 On the contrary, Abalymov et al used the method of thermal-annealing (T-A) of a solution of gellan gum (GG) at 65 °C for 16 h (Figure 8c). 47 As a result of prolonged exposure to high temperatures, the resulting hydrogel passes from a meshy form to a fibrillar one. Such transitions are carried out due to the crystallization of GG after passing through the polymer solubility limit.…”

“…With the understanding of the impact of different physical processes on the formation and modification of the hydrogel network, various strategies have been developed to align fibers in fibrillar hydrogels, such as mechanical stretching and compression, − electric field, − chemical gradient, , temperature (positive and negative), − magnetic field, − and flows (capillary and Marangoni flows). − These engineering approaches promote directed migration, specific cell morphology, and activation of certain genes through surface micro- and nanotopography.…”