Detection system based on magnetoelastic sensor for classical swine fever virus

• A magnetoelastic (ME) biosensor-based detection system for CSFV is presented.
• The concentration of CSFV suspension can be efficiently detected as the biosensor's resonant frequency signal.
• The test results prove that the biosensor's response is from the effective combination between anti-CSFV IgG and CSFV.
• The study demonstrates that the system can be used as the high-precision device to detect the CSFV.

In this paper, a magnetoelastic (ME) sensing system for the detection of classical swine fever virus (CSFV) is presented. The detection system comprises a test paper and a measurement circuit. The test paper consists mainly of an ME biosensor to detect the CSFV. Based on the impedance analysis technique, the measurement circuit is designed to measure the resonance frequency of the ME biosensor. The anti-CSFV IgG is immobilized onto the ME sensor surface to form the ME biosensor through a physical absorption approach. The experimental results show that the shift in the resonance frequency of the ME biosensor increases with the augmentation of the CSFV concentration. The effectiveness of the combination between the anti-CSFV IgG and CSFV is confirmed by the scanning electron microscopy (SEM) images, the sandwich-based enzyme-linked immunosorbent assay (ELISA) analysis, the interference study and the reference biosensor test method. The resonance frequency shift is linearly proportional to the concentration in the range from 0 to 2.5 μg/ml, and becomes sub-linear at higher concentrations. The ME biosensor for CSFV detection has a sensitivity of about 95 Hz/μg ·ml−1, with a detection limit of 0.6 μg/ml.