title: Role of the pH on hyaluronan behavior in aqueous solution.
abstract: In this paper, we have examined the behavior of hyaluronan solutions at different pH values. A slight degradation is observed in acidic conditions (pH = 1.6) and basic medium (pH = 12.6) from molecular weight distribution analysis, but the rheological behavior is relatively not influenced much by the pH at the exclusion of two domains: around pH = 2.5, a gel-like behavior is shown and is attributed to cooperative interchain interactions due to the reduction of the polymer net charge and may be the protonation of the acetamido groups; for pH > 12, the decrease of viscosity is mainly attributed to a reduction of the stiffness of the polymeric backbone in alkaline conditions due to the partial breakage of the H-bond network.
authors.affiliation: Centre de Recherches sur les Macromolécules Végétales, CNRS, affiliated to Joseph Fourier University, BP 53, 38041 Grenoble Cedex 9, France.
authors.forename: Iuliana
authors.initials: I
authors.lastname: Gatej
authors.forename: Marcel
authors.initials: M
authors.lastname: Popa
authors.forename: Marguerite
authors.initials: M
authors.lastname: Rinaudo
mesh_terms: D006820:Hyaluronic Acid / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D012212:Rheology; D014783:Viscosity; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D006820:Hyaluronic Acid