An Automated Magnetic Separation Device Coupled with a Fluorescent Biosensor for Detection of Antibiotic Residues

Highlights A practical magnetic separation device was designed, fabricated, and evaluated for enrofloxacin detection. Coupled with a fluorescent biosensor, the device could automatically process a sample in 50 min. The device performed incubation and magnetic separation using a pipette method. The device has the advantages of low-cost and feasibility for on-site detection. Abstract . Antibiotic residues have been a continuing concern in food safety, raising a great issue in human health. For rapid detection of antibiotics, an automated device was developed that can capture and separate a target analyte based on immunomagnetic beads. This automated separation device is suitable for separating the magnetic beads in a preprocessing step, with liquid transfer and magnetic enrichment functions. The device was combined with a fluorescent biosensor to simplify the cumbersome pretreatment of enrofloxacin. In our experiments, enrofloxacin in water samples was used as the detection object, and the entire process could be completed in less than 50 min with automated operation. The lower limit of detection reached 54 ng mL-1 (S/N = 3). The fluorescent biosensor has been enhanced with this automated separation device for more sensitive rapid detection of antibiotic residues in the food supply chain and environment. Keywords: Antibiotic detection, Automation, Fluorescent biosensor, Immunomagnetic separation, Sample pretreatment.