title: Elastin-like recombinamer catalyst-free click gels: characterization of poroelastic and intrinsic viscoelastic properties.
abstract: Elastin-like recombinamer catalyst-free click gels (ELR-CFCGs) have been prepared and characterized by modifying both a structural ELR (VKVx24) and a biofunctionalized ELR-bearing RGD cell-adhesion sequence (HRGD6) to bear the reactive groups needed to form hydrogels via a click reaction. Prior to formation of the ELR-CFCGs, azide-bearing and cyclooctyne-modified ELRs were also synthesized. Subsequent covalent crosslinking was based on the reaction between these azide and cyclooctyne groups, which takes place under physiological conditions and without the need for a catalyst. The correlation among SEM micrographs, porosity, swelling ratio, and rheological measurements have been carried out. The storage and loss moduli at 1Hz are in the range 1-10kPa and 100-1000Pa, respectively. The linear dependence of |G∗| on f(½) and the peak value of tan δ were considered to be consistent with a poroelastic mechanism dominating the frequency range 0.3-70Hz. The discrete relaxation spectrum was obtained from stress relaxation measurements (t>5s). The good fit of the relaxation modulus to decrease exponential functions suggests that an intrinsic viscoelastic mechanism dominates the transients. Several recombinamer concentrations and temperatures were tested to obtain gels with fully tuneable properties that could find applications in the biomedical field.
authors: G.I.R. BIOFORGE, Universidad de Valladolid, Centro I+D, Universidad de Valladolid, Paseo de Belén 11, 47011 Valladolid, Spain. Electronic address: igonzalez@bioforge.uva.es.
authors: Israel
authors: I
authors: González de Torre
authors: G.I.R. BIOFORGE, Universidad de Valladolid, Centro I+D, Universidad de Valladolid, Paseo de Belén 11, 47011 Valladolid, Spain.
authors: Mercedes
authors: M
authors: Santos
authors: G.I.R. BIOFORGE, Universidad de Valladolid, Centro I+D, Universidad de Valladolid, Paseo de Belén 11, 47011 Valladolid, Spain.
authors: Luis
authors: L
authors: Quintanilla
authors: G.I.R. BIOFORGE, Universidad de Valladolid, Centro I+D, Universidad de Valladolid, Paseo de Belén 11, 47011 Valladolid, Spain.
authors: Ana
authors: A
authors: Testera
authors: G.I.R. BIOFORGE, Universidad de Valladolid, Centro I+D, Universidad de Valladolid, Paseo de Belén 11, 47011 Valladolid, Spain.
authors: Matilde
authors: M
authors: Alonso
authors: G.I.R. BIOFORGE, Universidad de Valladolid, Centro I+D, Universidad de Valladolid, Paseo de Belén 11, 47011 Valladolid, Spain.
authors: José Carlos
authors: JC
authors: Rodríguez Cabello
mesh_terms: D000595:Amino Acid Sequence; D002384:Catalysis; D004548:Elasticity; D004549:Elastin / Q000737:chemistry*; D020100:Hydrogels; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D016062:Porosity; D014783:Viscosity
chemical_list: D020100:Hydrogels; D004549:Elastin
keywords: Catalyst-free click chemistry; ELRs; Fluid-independent viscoelasticity; Poroelasticity