Abstract: A method of electroporation of a biological object, comprises: introducing a carrier particle into a medium containing the biological object; applying a first electric field to the medium to induce trapping of the biological object by the carrier particle; and varying at least one parameter of the first electric field so as to induce electroporation of the biological object.

Abstract: Apparatus (20) for use with a biological sample, including at least one viable sperm cell (12) having a tail (8) and a head (6), comprising: a fluid chamber (40) shaped and sized for receiving the biological sample, and at least one electrode (80) coupled to the chamber and in operable communication with an electric source for applying alternating current (AC) to drive the at least one electrode (80) to generate a dielectrophoresis (DEP) force in the chamber. In response to the DEP force: (i) the tail of the at least one viable sperm cell is attracted to the electrode and pulled into proximity to the electrode, and simultaneously (ii) the head is repelled and distanced from the electrode such that a proximity of the tail to an edge of the electrode is greater than a proximity of the head to the edge of the electrode. Other applications are also described.

Abstract: A sensor system comprises a permselective medium positionable to contact a fluid in a microchannel, an arrangement of electrodes arranged to generate an electric field across the permselective medium, an ion concentration sensing system having a sensing element configured to provide sensing signals indicative of a local ion concentration pattern, and a signal processor for analyzing a sensing signal received from the ion concentration sensing system to determine at least one flow parameter characterizing the flow.

Abstract: A method for dielectrophoresis includes applying an electric field across a micro-fluidic chamber with an alternating current (AC), trapping the target particles on the at least one carrier particle, transporting the target particles from a first location in the chamber to a second location in the chamber distanced from the first location with the at least one carrier particle and dynamically controlling the trapping and the transporting based on remotely applying forces on the at least one carrier particle. The trapping is based on localized gradients of the electric field induced by the carrier particle. The applied electric field is uniform absent a carrier particle present in the micro-fluidic chamber. The micro-fluidic chamber contains an electrolyte-solution with suspended target particles and at least one carrier particle freely floating on or in the electrolyte-solution.

Abstract: A microchannel-membrane device comprises a microchannel extending through at least one electrode, the microchannel having a predetermined depth; an ionic permselective medium, such as a membrane, across the microchannel between the electrodes; and a heater, or array of heaters, embedded below the microchannel on at least one side of the permselective membrane. The heaters can be either prefabricated or dynamically patterned using laser illumination with/without photoconductive coating. The heaters are on the depletion side of the membrane and induce a vortex which limits the growth of the diffusion area. Operation of the heaters allows for controlled positioning of the end of the diffusion area and with it also the position of the preconcentrated molecule plug.

Abstract: A method for dielectrophoresis includes applying an electric field across a micro-fluidic chamber with an alternating current (AC), trapping the target particles on the at least one carrier particle, transporting the target particles from a first location in the chamber to a second location in the chamber distanced from the first location with the at least one carrier particle and dynamically controlling the trapping and the transporting based on remotely applying forces on the at least one carrier particle. The trapping is based on localized gradients of the electric field induced by the carrier particle. The applied electric field is uniform absent a carrier particle present in the micro-fluidic chamber. The micro-fluidic chamber contains an electrolyte-solution with suspended target particles and at least one carrier particle freely floating on or in the electrolyte-solution.

Abstract: A sensor system comprises a permselective medium positionable to contact the fluid in the microchannel, an arrangement of electrodes arranged to generate an electric field across the permselective medium, an ion concentration sensing system having a sensing element configured to provide sensing signals indicative of a local ion concentration pattern, and a signal processor for analyzing a sensing signal received from the ion concentration sensing system to determine at least one flow parameter characterizing the flow.

Abstract: A microchamber electrochemical cell and method of using the cell for performing quantitative analysis of various charged macromolecules is presented. The microchamber electrochemical cell includes a substrate, opposing electrodes and at least one nanoslot. The substrate is configured to define a pair of opposing fluid reservoirs. The pair of opposing electrodes are respectively positioned within the opposing fluid reservoirs. Each nanoslot is configured to fluidly connect the opposing fluid reservoirs together. The opposing fluid reservoirs of the microchamber electrochemical cell are fluidly connected to each other only through each nanoslot. Each nanoslot is physically restricted to less than 500 nanometers. One method includes the steps of coupling, filling, measuring, obtaining, performing and preparing.

Abstract: A microchamber electrochemical cell and method of using the cell for performing quantitative analysis of various charged macromolecules is presented. The microchamber electrochemical cell includes a substrate, opposing electrodes and at least one nanoslot. The substrate is configured to define a pair of opposing fluid reservoirs. The pair of opposing electrodes are respectively positioned within the opposing fluid reservoirs. Each nanoslot is configured to fluidly connect the opposing fluid reservoirs together. The opposing fluid reservoirs of the microchamber electrochemical cell are fluidly connected to each other only through each nanoslot. Each nanoslot is physically restricted to less than 500 nanometers. One method includes the steps of coupling, filling, measuring, obtaining, performing and preparing.