title: Rotational microrheology of Maxwell fluids using micron-sized wires.
abstract: We demonstrate a simple method for rotational microrheology in complex fluids using micrometric wires. The three-dimensional rotational Brownian motion of the wires suspended in Maxwell fluids is measured from their projection on the focal plane of a microscope. We analyze the mean-squared angular displacement of the wires of length between 1 and 40 μm. The viscoelastic properties of the suspending fluids are examined from this analysis and found to be in good agreement with macrorheology data. Viscosities of simple and complex fluids between 10(-2) and 30 Pa s could be measured. As for the elastic modulus, values up to ∼5 Pa could be determined. This simple technique, allowing for a broad range of probed length scales, opens new perspectives in microrheology of heterogeneous materials such as gels, glasses and cells.
authors.affiliation: Laboratoire Matière et Systèmes Complexes (MSC), UMR CNRS 7057 & Université Paris Diderot, France. berengere.abou@univ-paris-diderot.fr.
authors.forename: Rémy
authors.initials: R
authors.lastname: Colin
authors.forename: Loudjy
authors.initials: L
authors.lastname: Chevry
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Berret
authors.forename: Bérengère
authors.initials: B
authors.lastname: Abou
mesh_terms: D004548:Elasticity; D008823:Micelles; D012212:Rheology; D012399:Rotation; D014783:Viscosity
chemical_list: D008823:Micelles