Person: Martínez López, Genoveva
Universidad Complutense de Madrid
Faculty / Institute
Now showing 1 - 2 of 2
PublicationDielectric characterization of bacterial cells using dielectrophoresis(Wiley-Liss, 2007-07) Sanchis, A.; Sancho Ruíz, Miguel; Martínez López, Genoveva; Sebastián Franco, José Luis; Muñoz San Martín, Sagrario; Miranda Pantoja, José MiguelMeasurements of dielectrophoretic collection spectra of Escherichia coli and Staphylococcus aureus suspensions are used for obtaining dielectric characteristics of both types of bacteria. The experiments are interpreted using a numerical method that models the cells as compartmented spherical or rod-like particles. We show the usefulness of this simple method to extract significant information about the electrical properties of Gram-negative and -positive bacteria. PublicationElectromechanical effects on multilayered cells in nonuniform rotating fields(American Physical Society, 2011-07-28) Sebastián Franco, José Luis; Muñoz San Martín, Sagrario; Sancho Ruíz, Miguel; Martínez López, Genoveva; Álvarez Galindo, GabrielWe use the Maxwell stress tensor to calculate the dielectrophoretic force and electrorotational torque acting on a realistic four-shelled model of the yeast Saccharomyces cerevisiae in a nonuniform rotating electric field generated by four coplanar square electrodes. The comparison of these results with numerical calculations of the dipolar and quadrupolar contributions obtained from an integral equation for the polarization charge density shows the effect of the quadrupole contribution in the proximity of the electrode plane. We also show that under typical experimental conditions the substitution of the multilayered cell by an equivalent cell with homogeneous permittivity underestimates the quadrupole contribution to the force and torque by 1 order of magnitude.