Impedance based apparatuses and methods for analyzing cells and particles

A method for monitoring the migration or invasion of a cell, the method comprising:

• a) providing a device comprising:
• i) an upper chamber adapted to receive and retain a cell sample;
• ii) a lower chamber comprising at least two electrodes;
• iii) a biocompatible porous membrane having a porosity sufficient to allow cells to migrate therethrough, wherein said membrane is disposed in the device so as to separate the upper and lower chambers from one another, wherein said at least two electrodes are disposed on said membrane;
• wherein migration of cells through the porous membrane permits contact between the migrating cells and one or more of at least two electrodes of said lower chamber, wherein said at least two electrodes have substantially the same surface area, and further wherein said contact at any one or more of said at least two electrodes provides a detectable change in impedance between or among the electrodes;
• b) introducing the cells into the upper chamber of the device;
• and,
• c) determining whether a change in impedance between or among the electrodes occurs, where a change in impedance between or among the electrodes is indicative of the invasion of, or migration of cells into or through, the biocompatible porous membrane.

A device comprising a device for measuring electrical impedance, resistance, or capacitance of a cell/substrate interface, comprising at least four electrodes having substantially the same surface area fabricated on one side of a flexible biocompatible membrane that comprises at least one pore,

• wherein said at least four electrodes are arranged in an electrode structure array of two or more interdigitated electrode structure units (IDES) or concentric electrode structure units (CCES), each of which comprises at least two electrodes,
• further wherein said device has a surface suitable for cell attachment or growth,
• further wherein cell attachment or growth results in cellular contact with at least one of said at least two electrodes further resulting in a detectable change in electrical impedance, resistance or capacitance,
• further wherein said biocompatible membrane is reversibly or irreversibly attached to a structure that provides a plurality of isolated fluid containers such that at least one of the fluid containers comprises a single IDES or CCES structure unit, wherein for each of said plurality of isolated fluid containers that comprises a single IDES or CCES, the exposed surface area of said one side of said biocompatible membrane on which electrodes are fabricated comprises an approximately uniform distribution of electrodes or electrode elements.