Blind Laboratory Trials for Multiple Pathogens in Spiked Food Matrices

Abstract

Previously developed assays for Salmonella typhimurium and staphylococcal enterotoxin B (SEB) were combined into a single multiplexed test and integrated into a fully automated prototype of the NRL Array Biosensor. Tests were performed on 216 blind samples of water, apple juice, and milk spiked with SEB (1–10,000 pg/ml) and S. typhimurium (5×10³−5×10⁷ colony‐forming units/ml). SEB and S. typhimurium were routinely detected in both water and apple juice at 100 pg/ml and 5×10⁵ colony‐forming units/ml respectively. Inclusion of milk as a sample matrix decreased the sensitivity of the assays by an order of magnitude.

Keywords:

• Immunosensor
• biosensor
• salmonella
• SEB
• pathogen detection

The authors thank Dr. John Callahan (FDA‐CFSAN) for preparing the spiked samples. This work was funded by the Food and Drug Administration (grant # FDU‐002245‐01). The views expressed here are those of the authors and do not represent those of the U.S. Navy, the U.S. Department of Defense or the U.S. Government.