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This paper presents an investigation of a fluidic-based impedance biosensor for rapid and accurate detection of Salmonella Typhimurium in raw chicken carcass rinsate. The biosensor is engineered with multiple distinct regions that concentrates Salmonella antigens to a detectable level, subsequently trapping the concentrated Salmonella samples on top of the detection interdigitated electrode array coated with a specific Salmonella antibody, maximizing the number of captured antigens. Detection is achieved through the antibody-antigen binding process, where binding events changes impedance values, providing a reliable method for identifying and quantifying Salmonella. The biosensor demonstrated a low limit of detection (LOD) of 1–2 cells/ml within 40–50 min. The findings demonstrated that the biosensor distinguishes low concentrations of live Salmonella cells, even in the presence of high concentrations of dead Salmonella cells, and non-specific binding pathogens viz., Listeria monocytogenes and E. coli O157:H7.
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This content will become publicly available on March 20, 2026
Impedance-based biosensor for rapid detection and identification of Salmonella in turkey products
This study presents the development of a highly sensitive microfluidic-based impedance biosensor designed for rapid detection and identification of Salmonella Infantis in raw turkey samples, with a limit of detection (LOD) as low as 1 CFU/ml in 70 minutes detection time. The biosensor is equipped with novel focusing and trapping regions, significantly enhancing its sensitivity by concentrating and trapping Salmonella cells in the detection region. Salmonella cells labeled with fluorescent dyes were used to validate the functionality of the focusing and trapping mechanism, confirming the biosensor's ability to concentrate and trap Salmonella cells.
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- PAR ID:
- 10650696
- Editor(s):
- Rapp, Bastian E; Dalton, Colin
- Publisher / Repository:
- SPIE
- Date Published:
- Page Range / eLocation ID:
- 29
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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