Effects of cryo-processing on the mechanical and biological properties of poly(vinyl alcohol)-gelatin theta-gels

Abstract

Poly(vinyl alcohol) (PVA), a synthetic, nontoxic polymer, is widely studied for use as a biomedical hydrogel due to its structural and physicomechanical properties. Depending on the synthesis method, PVA hydrogels can exhibit a range of selected characteristics-strength, creep resistance, energy dissipation, degree of crystallinity, and porosity. While the structural integrity and behavior of the hydrogel can be finetuned, common processing techniques result in a brittle, linear elastic material. In addition, PVA lacks functionality to engage and participate in cell adhesion, which can be a limitation for integrating PVA materials with tissue in situ. Thus, there is a need to further engineer PVA hydrogels to optimize its physicomechanical properties while enhancing cell adhesion and bioactivity. While the inclusion of gelatin into PVA hydrogels has been shown to impart cell-adhesive properties, the optimization of the mechanical properties of PVA-gelatin blends has not been studied in the context of traditional PVA hydrogel processing techniques. The incorporation of poly(ethylene glycol) with PVA prior to solidification forms an organized, cell instructive hydrogel with improved stiffness. The effect of cryo-processing, i.e., freezethaw (FT) cycling was elucidated by comparing 1 FT and 8 FT theta-cryo-gels and cryo-gels. To confirm the viability of the gels, human mesenchymal stem cell (hMSC) protein and sulfated glycosaminoglycan assays were performed to verify the nontoxicity and influence on hMSC differentiation. We have devised an elastic PVA-gelatin hydrogel utilizing the theta-gel and cryo-gel processing techniques, resulting in a stronger, more elastic material with greater potential as a scaffold for complex tissues.

High strength and bioactivity polyvinyl alcohol/collagen composite hydrogel with tannic acid as cross‐linker

“…These composites can be used as scaffolds for cell cultures. [ 23,25,26 ] As the most abundant protein in mammal bodies, collagen (COL) is an ideal raw material for the tissue healing process due to good biocompatibility, biodegradability, and inductivity for cell proliferation. [ 27 ] However, it is difficult for COL to display its bioactivity due to degradation continuously.…”

Phyllanthus emblica‐Loaded Cryogels for Improved Wound Care: Characterization and In Vitro Studies

“…Pterostilbeneloaded PVA/Gel cryogels have been reported as a potential dressing material in wound therapy, promoting cell viability and proliferation. [48][49][50] However, it has been reported that PVA/Gel cryogel promotes the viability and proliferation of endothelial cells and is particularly suitable for vascular tissue engineering applications. [50] In addition, it was determined that there was no cytotoxic effect for human skin cells cultured in PVA/Gelatin cryogel and the scaffold exhibited good biocompatibility.…”

<strong><em></em></strong><em>Phyllanthus emblica</em> Loaded Cryogels for Improved Wound Care: Characterizationand In Vitro Studies

“…For these reasons, it has been reported to be a promising platform in tissue engineering. Pterostilbene-loaded PVA/Gel cryogels have been reported as a potential dressing material in wound therapy, promoting cell viability and proliferation [57][58][59]. However, it has been reported that PVA/Gel cryogel promotes the viability and proliferation of endothelial cells and is particularly suitable for vascular tissue engineering applications [59].…”