The Non-Linear Flow Properties of Snail Mucus

Abstract

Biopolymers in aqueous solution have a wide range of applications as their highly tailored designs lead to sophisticated material properties [1] for the daily fight of survival. Snails employ a unique combination of polysaccharides and proteins to produce a mucus with material properties that allow for the stunning capability to crawl on vertical walls or even overhead without loosing contact to the surface. In this paper we present rheological investigations [2] of the material properties of minute amounts of mucus under nonlinear deformation conditions as they are created under the snail foot. For this purpose we present a new technique [3] that enables the investigation in natural film thicknesses of 10 – 20 m. The time and strain-dependent structural changes of the complex mucus gels, presented in the form of Pipkin diagrams [4], show how the deformation of the snail foot exploits the physically-crosslinked structure of the aqueous mucin gels to obtain a maximum adhesion with minimum energy consumption during locomotion. 1. Clasen, C. and W.M. Kulicke, Rheo-optical studies of barley (1 -> 3)(1 -> 4)-beta-glucan solution: Detection of the flow behavior of aggregates in the sol state. Journal of Rheology, 2003. 47(2): p. 321-335. 2. Clasen, C. and W.M. Kulicke, Determination of viscoelastic and rheo-optical material functions of water-soluble cellulose derivatives. Progress in Polymer Science, 2001. 26(9): p. 1839-1919. 3. Clasen, C. and G.H. McKinley, Gap-Dependent Microrheometry of Complex Liquids. Journal of Non-Newtonian Fluid Mechanics, 2004. 124: p. 1-10. 4. Pipkin, A.C., Lectures on Viscoelasticity Theory. 1972, Heidelberg: Springer-Verlag.status: publishe