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Title: Microfluidic based impedance biosensor for pathogens detection in food products
Abstract

A MEMS‐based impedance biosensor was designed, fabricated, and tested to effectively detect the presence of bacterial cells includingE. coli O157:H7andSalmonella typhimurium in raw chicken products using detection region made of multiple interdigitated electrode arrays. A positive dielectrophoresis based focusing electrode was used in order to focus and concentrate the bacterial cells at the centerline of the fluidic microchannel and direct them toward the detection microchannel. The biosensor was fabricated using surface micromachining technology on a glass substrate. The results demonstrate that the device can detectSalmonellawith concentrations as low as 10 cells/mL in less than 1 h. The device sensitivity was improved by the addition of the focusing electrodes, which increased the signal response by a factor between 6 and 18 times higher than without the use of the focusing electrodes. The biosensor is selective and can detect other types of pathogen by changing the type of the antibody immobilized on the detection electrodes. The device was able to differentiate live from dead bacteria.

 
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PAR ID:
10462613
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
ELECTROPHORESIS
Volume:
40
Issue:
4
ISSN:
0173-0835
Page Range / eLocation ID:
p. 508-520
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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