Portable Press-Driven Magnetoelastic Biosensor for Detection of Escherichia coli in sewage

Escherichia coli (E. coli) in sewage can invade the human body via contaminated water and induce a variety of diseases, which may even cause death in severe cases. Existing detection methods are limited by high cost, high technical requirements, low sensitivity, long assay time, and complicated operation procedures. Therefore, it is imperative to develop high-sensitive biosensors capable of rapid, efficient, and on-site detection of E. coli. Accordingly, this study proposes a portable press-driven magnetoelastic (ME) biosensor. The system-on-chip of the ME chip is functionalized with an antibody/E. coli immunoassay recognition sensitive structure. The ME properties of Metglas 2826 chips enable quantitative quantification of E. coli concentration via the resonance frequency shift (RFS) responding to mass loading changes induced by antibody/E. coli immunocomplex. The portable press-driven biosensor comprises a T-shaped mold integrated with coil-wrapped reaction chambers embedded in a Metglas 2826 chip, alongside microfluidic channels and micro air chambers. This design realizes the integration of sampling and detection into one system. The developed biosensor exhibits a wide linear detection range for E. coli from 10 2 to 10 7 CFU/mL, with a detection limit of 10 2 CFU/mL. Collectively, this integrated ME sensing platform offers a low-cost, highly sensitive, and portable approach for on-site detection of E. coli in sewage. With its all-in-one sampling and detection capability, the sensor demonstrates great potential for on-site pathogen screening in wastewater monitoring and E. coli contamination control.