Magnetic nanoparticle‐based fluorescent immunoassay for determination of progesterone in milk

Abstract

A sensitive and rapid magnetic nanoparticle‐based fluorescent immunoassay (MNPs‐FIA) for determination of progesterone in raw milk was developed. The PG‐3‐CMO‐BSA and PG‐3‐CMO‐BSA‐FITC conjugates were obtained. The optimal amount of immobilised antibody on MNPs (0.375 mg) and optimal concentration of PG‐3‐CMO‐BSA‐FITC conjugate (7.5 μg/mL) for MNPs‐FIA were determined. The optimal time and temperature for progesterone MNPs‐FIA were found to be – 12 min and 37 °C. The analytical parameters of immunoassay in cow milk were in the concentration range 0.25‐25 ng/mL and detection limit of 0.065 ng/mL for progesterone. The MNPs‐FIA was applied to evaluate progesterone in three types of milk (UHT, pasteurised and raw cow's milk).