Channel-less separation of bioparticles on a bioelectronic chip by dielectrophoresis

An assay system, comprising:

• a reaction apparatus comprising:
• a microfabricated chip having a plurality of electrodes, each electrode having a surface coated with a permeation layer, the chip being mounted on a printed circuit board,
• a flow chamber comprising a first reaction area and a second reaction area within the flow chamber, wherein the first reaction area and the second reaction area are partially separated by a partition that is impermeable to a fluid, and wherein the flow chamber is mounted over the chip,
• a plurality of tubes coupled to the flow chamber, and
• an output connector for electrically coupling the reaction apparatus to a controller,
• a controller electrically coupled to the reaction apparatus,
• a pump coupled to the plurality of tubes, and
• a laser subsystem configured to deliver excitation energy to the electrodes.

A method of manipulating a biological sample comprising a mixture of desired and undesired cellular materials within a single apparatus including a chip, a first and second array of electrodes coated with a permeation layer, a channel-less flow chamber mounted over the chip and having a first reaction area corresponding to the first array of electrodes and a second reaction area corresponding to the second array of electrodes, and a laser subsystem configured to deliver excitation energy, wherein the first reaction area and the second reaction area are partially separated by a partition that is impermeable to a fluid, the method comprising:

• pumping separation buffer into the flow chamber,
• introducing the sample into the flow chamber,
• applying an electric current to the first array of electrodes to bias the electrodes in a checkerboard format, and to provide field maxima at each electrode and field minima between the electrodes, wherein desired materials are collected at the field maxima and undesired materials are collected at the field minima,
• washing away the undesired materials,
• staining the desired materials, and
• generating an image of the desired materials by using the laser subsystem to deliver excitation energy to the desired materials.