Synthesis, characterization and cytotoxicity of Chitosan/Polyvinyl Alcohol/Bioactive Glass hybrid scaffolds obtained by lyophilization

Abstract

One of the important research topics in tissue engineering is the development of optimum three-dimensional scaffolds for regeneration and growth of bone tissue. The scaffold developed should promote an initial biomechanical support, provide the formation, deposition and organization of the new organic matrix generated, and degrade proportionally to the growth of the new tissue. In this study hybrid scaffolds based on the blend Chitosan (CHI)/Poly (vinyl alcohol) (PVA), with two different CHI:PVA molar ratios (1:1, and 3:1), and Bioactive Glass as the inorganic phase, were developed by a sol-gel route, followed by lyophilization. The materials were cross-linked with Glutaraldehyde. The obtained porous scaffolds were characterized by SEM, FTIR, porosity measurements by Archimedes method, and compression test. The in vitro degradation was studied by immersion in simulated body fluid for several time periods and evaluation of mass loss. Citotoxicity analysis was carried out on samples as prepared and after immersion in PBS solution for 24hrs, using human fibroblast cells and MTT method to evaluate cell viability. The matrices obtained showed promising results, presenting about 96% porosity, pore size varying in the range 20-300 µm, and interconnected pores. The mass loss presented by the matrices with CHI/PVA ratios 3:1 and 1:1 during the degradation test in vitro, was around 10% after a week of testing, with macroscopic preservation of their physical structure. Cytotoxicity tests showed that the samples were toxic as produced and not toxic after treatment with PBS, showing this approach was suitable as a final preparation step of these samples.

Structural, mechanical and swelling characteristics of 3D scaffolds from chitosan-agarose blends

“…This was attributed to the nature of chitosan as a semicrystalline polymer that tends to form membrane parts within the pores and lead to reduction in the pore size (Yan et al, 2010). Moreover, the pore size of freeze-dried chitosan-polyvinyl alcohol (Ch-PVA) scaffolds was also investigated and it was found that the pore size of Ch 37.5-PVA 62.5 (wt%) was approximately 40% higher than Ch 16.7-PVA 83.3 scaffolds (Silva, Macedo, Coletta, Feldman, & Pereira, 2016).…”

Optimized Bioactive Glass: the Quest for the Bony Graft

“…Hence, the introduction of water needs to be limited to avoid a premature gelation of the BAG sol that would make it harder to process scaffolds. Because of this restraint, many hybrid scaffolds presented in the literature do not contain calcium and possess a limited bioactivity or they do not incorporate calcium due to the use of salts . Only a few hybrids with well‐incorporated calcium were obtained, but they were in the form of dense or fiber materials …”

Cellulosic/Polyvinyl Alcohol Composite Hydrogel: Synthesis, Characterization and Applications in Tissue Engineering

“…The characteristic signals of aldehyde groups currently found that around 1730 cm −1 or 2700 cm −1 do not appear in FT-IR charts of the formed hydrogels [ 52 ]. The presence of C-O vibrations at 1057 cm −1 supported by those found at 1160 cm −1 as well as the band at OH 890 cm −1 , respectively, were attributed to acetal and hemiacetal bonds [ 53 ].…”