Rheology of Gastric Mucin Exhibits a pH-Dependent Sol-Gel Transition
Journal Article

Published: Tuesday, April 03, 2007
Journal: Biomacromolecules, Volume 8, Number 5, Pages 1580

Authors (7 total): J. Celli, B. Turner, N. H. Afdhal, R. H. Ewoldt, G. H. McKinley, R. Bansil, S. Erramilli

Abstract: Gastric mucin, a high molecular weight glycoprotein, is responsible for providing the gel-forming properties and protective function of the gastric mucus layer. Bulk rheology measurements in the linear viscoelastic regime show that gastric mucin undergoes a pH-dependent sol-gel transition from a viscoelastic solution at neutral pH to a soft viscoelastic gel in acidic conditions, with the transition occurring near pH 4. In addition to pH-dependent gelation behavior in this system, further rheological studies under nonlinear deformations reveal shear thinning and an apparent yield stress in this material which are also highly influenced by pH.