Efectos electrocinéticos de células biológicas y partículas coloidales en la espectroscopia dieléctrica a bajas frecuencias

Abstract

The manipulation of nanometer-size biological cells or macromolecules (e.g. DNA) is an essential approach in recent nanotechnology, -hydride of biology, chemistry, and engineering-, which pretends the assembly of functional bionanostructures by means of a mechanical positioning of its components. On the other hand, provides the manipulation of these objects for a biomedical analysis and size separation into certain populations. Electrokinetic techniques at low frequency allow studying aggregation, rotation, deformation, and orientation, including manipulation, of small single objects in a wide frequency range between 1 Hz up to several MHz. The physics behind these techniques is based on impedance properties of particles or cells in suspension. The electrokinetic effects are consequence of the interaction between an incident electric a.c.-field and the induced dipole moment of the dielectric objects. In the present paper, we outline physical aspects behind different electrokinetic methods. The advanced state of lithographic techniques allows making microchambers suitable for both biochemical investigation and medical diagnostics. In particular point research activities in this field toward the fabrication of biosensors in a wide range of applications, including the integration of different biomedical and biochemical analysis aspects within a single “lab-on-a-chip”.