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Characterization of PVA/glutaraldehyde hydrogels obtained using Central Composite Rotatable Design (CCRD). | LitMetric

AI Article Synopsis

  • Hydrogels, made from natural or synthetic polymers, are being developed for biomedical uses, specifically to mimic the properties of the vitreous humor using polyvinyl alcohol (PVA) and glutaraldehyde (GLUT) as a cross-linker.
  • The study identified that a hydrogel formulation with 3.98% PVA and 3.13 mL GLUT achieved similar physicochemical properties to vitreous humor, including density, dynamic viscosity, and refractive index.
  • Additional analyses showed that GLUT cross-linking increased viscosity and glass transition temperature while decreasing swelling degree and crystallinity, resulting in a hydrogel that behaves like a Newtonian fluid with higher apparent viscosity than unmodified PVA.

Article Abstract

Hydrogels are made from natural or synthetic polymers and, currently, they have many biomedical applications. In this work, the conditions for obtaining a hydrogel with similar physicochemical characteristics to the vitreous humor were defined using polyvinyl alcohol (PVA) and glutaraldehyde (GLUT) as cross-linker. The concentration of PVA and GLUT were modified, and their effect was analyzed in terms of the refractive index, density, and dynamic viscosity. The hydrogel which was obtained using 3.98% (w/V) of PVA, 3.13 mL (1.57 g) of GLUT in 100 mL, and the initial pH of 7.2 showed similar characteristics to the vitreous humor (density = 1.0174 ± 0.0050 g mL , dynamic viscosity = 3.7425 ± 0.1800 mPa s and refractive index = 1.3410 ± 0.0010). The hydrogels were further investigated by rheological measurements, infrared spectroscopy, differential scanning calorimetry, X-ray diffraction and determination of swelling degree. The reticulation with GLUT promoted an increase in viscosity and glass transition temperature. On the other hand, it stimulated a decrease in the swelling degree, crystallinity, melting temperature, and intensity of the band related to the -OH bond, compared with the PVA without reticulation. The reticulated hydrogel displayed Newtonian behavior and a higher apparent viscosity than the PVA. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1558-1566, 2018.

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http://dx.doi.org/10.1002/jbm.b.33958DOI Listing

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