title: Frequency dependence of the shear moduli of spectrin studied using a multiple lumped resonator viscoelastometer.
abstract: The frequency dependence (119-7860 Hz) of the storage and loss shear moduli, G' and G'', of human erythrocyte spectrin dimer crude solutions at 22.5 degrees C has been measured using a Birnboim-Schrag multiple lumped resonator viscoelastometer. The measurements were carried out on solutions of ionic strength 1 mM containing 1.1-3.7 mg ml-1 spectrin. This corresponds to the terminal zone for G' and G''. Analysis of the data using the standard theory of hybrid relaxation spectra yields a relaxation time of 22.5 +/- 1 microseconds. The pure spectrin dimer relaxation time is estimated to be 16 +/- 3 microseconds. This result suggests that at an ionic strength of 1 mM, the spectrin dimers are extended and that the main relaxation process is simple end-over-end rotation.
authors.affiliation: Department of Physics and Mathematics, Norwegian Institute of Technology, University of Trondheim.
authors.forename: M L
authors.initials: ML
authors.lastname: Sandvold
authors.forename: A
authors.initials: A
authors.lastname: Mikkelsen
authors.forename: A
authors.initials: A
authors.lastname: Elgsaeter
mesh_terms: D001703:Biophysics / Q000295:instrumentation; D001704:Biopolymers; D004548:Elasticity; D004910:Erythrocyte Membrane / Q000737:chemistry; D006801:Humans; D011487:Protein Conformation; D013049:Spectrin / Q000737:chemistry* / Q000302:isolation & purification; D014783:Viscosity
chemical_list: D001704:Biopolymers; D013049:Spectrin