This paper presents a portable magnetoelastic (ME) biosensor system that enables rapid, on-site detection of pathogenic bacteria. The system utilizes a patented portable resonant frequency analyzer and two 1 mm long ME biosensors (biosensors coated with and without phage binding a specific pathogen) enabling real-time measurement of resonant frequency changes. By comparing the response of the biosensors, the presence of the specific pathogen can be detected. In this work, detection of Salmonella Typhimurium cells was demonstrated, and it was found that down to 2,500 cfu can be detected in less than 10 min. The detection limit can be improved by using a smaller sensor (e.g., 500 um long sensors) and an optimal chamber design increasing the probability of bacterial cells striking the biosensor surface.
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