Targeted cell detection based on microchannel gating

Abstract

Currently, microbiological techniques such as culture enrichment and various plating techniques are used for detection of pathogens. These expensive and time consuming methods can take several days. Described below is the design, fabrication, and testing of a rapid and inexpensive sensor, involving the use of microelectrodes in a microchannel, which can be used to detect single bacterial cells electrically (label-free format) in real time. As a proof of principle, we have successfully demonstrated real-time detection of target yeast cells by measuring instantaneous changes in ionic impedance. We have also demonstrated the selectivity of our sensors in responding to target cells while remaining irresponsive to nontarget cells. Using this technique, it can be possible to multiplex an array of these sensors onto a chip and probe a complex mixture for various types of bacterial cells.

Surface-enhanced Raman scattering (SERS) for detection of phenylketonuria for newborn screening

“…Various miniaturization techniques have been introduced for detection of proteins [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20], nucleic acids [10,16,21], and cells [22][23][24][25][26][27]. These techniques are unsuitable for metabolites because tagging the metabolite with beads or a fluorophore would alter the structure significantly and affect the binding of the target metabolite to the probe antibody.…”

A Microfluidic Platform for Characterization of Protein–Protein Interactions

“…In a previous study, we have demonstrated the ability of this technique to detect target cells without the need for any labeling [22]. We have demonstrated the detection selectivity of this technique for glycoprotein–glycoprotein interactions, antibody-antigen interactions, and also antigen-glycoprotein interactions by choosing specific examples.…”

Electrical detection of protein biomarkers using bioactivated microfluidic channels

“…In a previous study we had demonstrated the ability of this technique to detect target cells without the need for any labeling 31. The purpose of this study was to investigate use of the described technique for specific protein biomarker detection.…”