title: Generation of focused electric field patterns at dielectric surfaces.
abstract: We here report on a concept for creating well-defined electric field gradients between the boundaries of capillary electrode (a capillary of a nonconducting material equipped with an interior metal electrode) outlets, and dielectric surfaces. By keeping a capillary electrode opening close to a boundary between a conducting solution and a nonconducting medium, a high electric field can be created close to the interface by field focusing effects. By varying the inner and outer diameters of the capillary, the span of electric field strengths and the field gradient obtained can be controlled, and by varying the slit height between the capillary rim and the surface, or the applied current, the average field strength and gradient can be varied. Field focusing effects and generation of electric field patterns were analyzed using finite element method simulations. We experimentally verified the method by electroporation of a fluorescent dye (fluorescein diphosphate) into adherent, monolayered cells (PC-12 and WSS-1) and obtained a pattern of fluorescent cells corresponding to the focused electric field.
authors: Department of Chemistry and Bioscience, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.
authors: Jessica
authors: J
authors: Olofsson
authors: Mikael
authors: M
authors: Levin
authors: Anette
authors: A
authors: Strömberg
authors: Stephen G
authors: SG
authors: Weber
authors: Frida
authors: F
authors: Ryttsén
authors: Owe
authors: O
authors: Orwar
mesh_terms: D000818:Animals; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods*; D004574:Electromagnetic Fields; D004594:Electrophysiology / Q000295:instrumentation / Q000379:methods; D008839:Microelectrodes; D009474:Neurons / Q000502:physiology; D016716:PC12 Cells; D051381:Rats