A highly sensitive microfluidic biosensor for rapid and accurate detection of Salmonella in raw chicken products
Mohammed Almalaysha, Arshdeep Singh, Sura A. Muhsin, Anna V. Carlson, Kate Trout, Amit Morey, Shuping Zhang, Lakshmikantha H. Channaiah, Mahmoud Almasri
Abstract
• The limit of detection is 1-2 cells/ml in chicken carcass wash spiked with Salmonella • The overall detection time is 40-50 min. • The addition of the focusing and trapping regions significantly enhanced the sensitivity • The device differentiated live from dead Salmonella cells. • The device demonstrated high specificity and selectivity. 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 minutes. 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 .