Hydrogels based on chemically modified poly(vinyl alcohol) (PVA-GMA) and PVA-GMA/chondroitin sulfate: Preparation and characterization

Abstract

This work reports the preparation of hydrogels based on PVA-GMA, PVA-GMA is poly(vinyl alcohol) (PVA) functionalized with vinyl groups from glycidyl methacrylate (GMA), and on PVA-GMA with different content of chondroitin sulfate (CS). The degrees of swelling of PVA-GMA and PVA-GMA/CS hydrogels were evaluated in distilled water and the swelling kinetics was performed in simulated gastric and intestinal fluids (SGF and SIF). PVA-GMA and PVAGMA/CS hydrogels demonstrated to be resistant on SGF and SIF fluids. The elastic modulus, E, of swollen-hydrogels were determined through compressive tests and, according to the obtained results, the hydrogels presented good mechanical properties. At last, the presence of CS enhances the hydrogel cell compatibility as gathered by cytotoxicity assays. It was concluded that the hydrogels prepared through this work presented characteristics that allow them to be used as biomaterial, as a carrier in drug delivery system or to act as scaffolds in tissue engineering as well

A cost effective hydrogel test kit for pre and post blast trinitrotoluene

“…Although glutaraldehyde is a common bifunctional agent [29,34], its toxicity and the non-uniformity of the obtained matrix [19] were matters of concern. The optimization studies found that 1mL of 5% w/v PVA solution, 1mL of 0.25 molL -1 KOH as a colourimetric reagent, and 25µL of EGDE provided an elastic hydrogel (Fig.…”

“…A three-dimensional cross-linked PVA network, PVA hydrogel, can absorb and retain large amounts of water and biological fluids [19]. It can be used to prepare a stimulus-sensitive material, capable of detecting, for example, pH, temperature, pressure, stress, ionic strength, electric field and light [20,21].…”

In-Situ UV-Photopolymerized PVA-g-GMA Hydrogels for Biomedical Applications: I. Synthesis, Characterizations and Grafting Optimization

“…This fact was attributed to the augment in the degree of crosslinking in the hydrogel matrix due to DS rising. Higher DS means high amount of methacrylate groups attached on PVA chains (Crispim et al, 2012), where the initiated sites on PVA consequently increase and a large number of monomer moieties have been attached. The highest GP% and GE% were achieved at 77% and 96%, respectively at [-OH (PVA)/GMA]: (1/0.25 M).…”

“…by UV-light. The esterification reaction occurred previously by the reaction between hydroxyl groups of PVA and GMA for modifying PVA (Crispim et al, 2012;Martens andAnseth, 2000 andZhao et al, 2010). Chemical modification of hydroxylated compounds by the insertion of GMA and its posterior crosslinking has been accomplished as an alternative hydrogel synthesis pathway.…”

“…Over sixty years, hydrogels have been used in numerous biomedical disciplines, in ophthalmology as contact lenses and in surgery fields. These hydrogels facilitate the localized and sustained drug release as they have muco-adhesive and bio-adhesive characteristics that improve drug stability time and tissue permeability and can make them excellent drug delivery vehicles (Bhattarai et al, 2010 andHamidi et al, 2008). Gelation process can take place by either chemical or physical crosslinking (association, aggregation, crystallization, complexation, and hydrogen bonding) that are reversible due to the conformational changes.…”