Abstract: Systems, apparatus and methods for designing and operating a cell-electrode impedance sensor to detect chemical and biological samples, including biological cells. In one implementation, a method of designing a cell-electrode impedance sensor includes determining a cell free cell-electrode impedance and a cell covered cell-electrode impedance based on a design model for the cell-electrode impedance sensor, wherein the design model is based on one or more factors, the factors including properties and elements of a cell-electrode impedance measurement system, using the cell free cell-electrode impedance and the cell covered cell-electrode impedance to obtain a sensor sensitivity of the cell-electrode impedance measurement system, and choosing one or more design parameters of the cell-electrode impedance sensor in the cell-electrode impedance measurement system to maximize the sensor sensitivity.

Abstract: Systems, apparatus and methods for designing and operating a cell-electrode impedance sensor to detect chemical and biological samples, including biological cells. In one implementation, a method of designing a cell-electrode impedance sensor includes determining a cell free cell-electrode impedance and a cell covered cell-electrode impedance based on a design model for the cell-electrode impedance sensor, wherein the design model is based on one or more factors, the factors including properties and elements of a cell-electrode impedance measurement system, using the cell free cell-electrode impedance and the cell covered cell-electrode impedance to obtain a sensor sensitivity of the cell-electrode impedance measurement system, and choosing one or more design parameters of the cell-electrode impedance sensor in the cell-electrode impedance measurement system to maximize the sensor sensitivity.

Abstract: Methods and apparatus for designing and measuring a cell-electrode impedance sensor to detect chemical and biological samples, including biological cells. The method of designing a cell-electrode impedance sensor comprises: determining a cell free cell-electrode impedance and a cell-covered cell-electrode impedance; obtaining a sensor sensitivity of the cell-electrode impedance measurement system; and choosing one or more design parameters of the cell-electrode impedance sensor to maximize the sensor sensitivity. When the frequency of AC signal between electrodes ranges from 10 kHz to 40 kHz, the sensitivity of the sensor is maximized.

Abstract: In a method and apparatus for separating a multiphase mixture, separable into discrete density phases, a circular bowl (2) is rotatable about a central axis and has an opening through which the mixture is introduced into the bowl (2). The rotation of the bowl (2) separates the mixture to form annular rings of the discrete density phases and a collection assembly (14) removes the separated discrete density phases. The collection assembly (14) is movable with respect to the bowl (2) such that the collection assembly (14) can be positioned in the bowl (2) to sequentially selectively and individually remove the annular columns from the bowl (2) while the bowl (2) is rotating substantially without disturbing the remaining annular columns within the bowl (2).