A novel electrochemical immunosensor for virginiamycin M1 determination based on Zinc 2-methylimidazole MOF modified with silver nanoparticles

A novel electrochemical immunosensor was proposed for rapid determination of virginiamycin M1 (VIR M1). To enhance the sensitivity, anti-VIR M1 monoclonal antibody (mAb) and silver nanoparticles-Zinc 2-methylimidazole MOF (AgNPs-ZIF-8) nanocomposite were used as bio-recognition element and electrode modification material for signal amplification, respectively. The characterization of nanocomposite was performed using ultraviolet visible spectrophotometry (UV–Vis), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Under optimal conditions, proposed immunosensor achieved quantitative detection of VIR M1 in range from 0.4 to 20 ng/mL, with a detection limit (LOD) of 0.32 ng/mL. The immunosensor was applied to feed and food of animal origin with recoveries ranging from 90.51 % to 101.17 %, featuring RSDs within 2.8 % to 8.8 %. Therefore, the immunosensor could be a promising tool for determining VIR M1 levels in feed and residues in food of animal origin.