title: Low viscosity hydrogel of guar gum: preparation and physicochemical characterization.
abstract: Guar gum was cross-linked with glutaraldehyde and characterized by GPC, rheology, WADX, SEM and TGA. This guar gum is a galactomannan polysaccharide, that contains small amount of arabinose, glucose and uronic acid, besides galactose and mannose. The polymer has high molar mass, with Mw, Mn and Mv values of 2.0x10(6), 1.2x10(6) and 1.9x10(6)g/mol, respectively. The reticulation follows a slow process and lead to a viscosity increase of 40 times compared with the original gum solution. The final viscosity was similar to that of Hylan G-F 20, a hyaluronate derivative, commercially used in viscosupplementation treatment. The gel contains 95.6% of water and the amount of residual glutaraldehyde is much lower than the LD-50. Porous structure was detected by SEM and thermal stability was improved by the cross-linking. The low viscosity, the small amount of remained glutaraldehyde, and the thermal stability indicates that the guar hydrogel has potential to be applied as biomaterial with specific rheological requirements.
authors.affiliation: Departamento de Química Orgânica e Inorgânica, Universidade Federal do Ceará, C. Postal 12.200, 60.455-760 Fortaleza, CE, Brazil.
authors.forename: Pablyana L R
authors.initials: PL
authors.lastname: Cunha
authors.forename: Rondinelle R
authors.initials: RR
authors.lastname: Castro
authors.forename: Francisco A C
authors.initials: FA
authors.lastname: Rocha
authors.forename: Regina C M
authors.initials: RC
authors.lastname: de Paula
authors.forename: Judith P A
authors.initials: JP
authors.lastname: Feitosa
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D001688:Biological Products / Q000737:chemistry; D005685:Galactans / Q000737:chemistry*; D005690:Galactose / Q000031:analogs & derivatives; D005976:Glutaral / Q000737:chemistry; D006358:Hot Temperature; D006820:Hyaluronic Acid / Q000031:analogs & derivatives / Q000737:chemistry; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D020100:Hydrogels; D007700:Kinetics; D008351:Mannans / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008970:Molecular Weight; D009005:Monosaccharides / Q000737:chemistry; D053149:Plant Gums; D011108:Polymers / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry; D012212:Rheology; D013696:Temperature; D028725:Theology; D013818:Thermogravimetry; D014783:Viscosity; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D001672:Biocompatible Materials; D001688:Biological Products; D005685:Galactans; D020100:Hydrogels; D008351:Mannans; D009005:Monosaccharides; D053149:Plant Gums; D011108:Polymers; D011134:Polysaccharides; D014867:Water; C012990:galactomannan; C049816:hylan; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D006820:Hyaluronic Acid; C007894:guar gum; D005976:Glutaral; D005690:Galactose