title: Portable Cytometry Using Microscale Electronic Sensing.
abstract: In this manuscript, we present three different micro-impedance sensing architectures for electronic counting of cells and beads. The first method of sensing is based on using an open circuit sensing electrode integrated in a micro-pore, which measures the shift in potential as a micron-sized particle passes through. Our micro-pore, based on a funnel shaped microchannel, was fabricated in PDMS and was bound covalently to a glass substrate patterned with a gold open circuit electrode. The amplification circuitry was integrated onto a battery-powered custom printed circuit board. The second method is based on a three electrode differential measurement, which opens up the potential of using signal processing techniques to increase signal to noise ratio post measurement. The third architecture uses a contactless sensing approach, which significantly minimizes the cost of the consumable component of the impedance cytometer. We demonstrated proof of concept for the three sensing architectures by measuring the detected signal due to the passage of micron sized beads through the pore.
authors.affiliation: Electrical Engineering and Computer Science Department, University of California Berkeley, Berkeley, CA, USA; School of Medicine, Stanford University, Stanford, CA, USA.
authors.forename: Sam
authors.initials: S
authors.lastname: Emaminejad
authors.affiliation: School of Medicine, Stanford University, Stanford, CA, USA.
authors.forename: Kee-Hyun
authors.initials: KH
authors.lastname: Paik
authors.affiliation: University of Ottowa Department of Physics, Ottowa, ON,Canada.
authors.forename: Vincent
authors.initials: V
authors.lastname: Tabard-Cossa
authors.affiliation: Electrical and Computer Engineering Department, Rutgers University, Piscataway, NJ, USA.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Javanmard