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Updated: Aug 29, 2025
Foodborne Pathogen Screening Using Magneto-fluorescent Nanosensor: Rapid Detection of E. Coli O157:H7
Published on: September 17, 2017
A phage-based magnetic relaxation switching biosensor using bioorthogonal reaction signal amplification for
Chenxi Huang1, Junpeng Zhao2, Rongsheng Lu3
1Key Laboratory of Environment Correlative Dietology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Department of Food Science, Cornell University, Ithaca, NY 14853, USA.
Abstract:
Phages are uniquely suited for bacterial detection due to their low cost and ability to recognize live bacteria. Herein, our work establishes the proof-of-concept detection of Salmonella in orange juice based on a phage-mediated portable magnetic relaxation switching (MRS) biosensor. The limit of quantification (LOQ) could reach 5 CFU/mL (95 % confidence interval [CI]: 4-7, N = 4) with a linear range of 102-108 CFU/mL, which has improved 10-fold than that without bioorthogonal signal amplification. The recovery rate of the phage-based MRS biosensor was 95.0 % (95 % confidence interval [CI]: 89.0 %-100.9 %, N = 6). The specificity of the phage-based MRS biosensor was 100 % without false-positive results. In addition, this sensor was able to detect <10 CFU per 25 mL of Salmonella in orange juice with 4-h pre-enrichment. The result from the phage-based MRS biosensor is consistent with that from the standard plate count method. This sensor provides a reliable and ultrasensitive detection platform for pathogens.
