METHOD OF DETERMINING TETRACYCLINES USING A PIEZOELECTRIC SENSOR Russian patent published in 2019 - IPC G01N33/543 

FIELD: chemistry.

SUBSTANCE: invention relates to analytical chemistry and can be recommended for selective summary determination of tetracyclines in food products and combined preparations using a piezoelectric immunosensor. Disclosed is a method for total determination of tetracycline antibiotics using a piezoelectric immunosensor, characterized in that a sensor surface is coated with a substrate based on self-assembled monolayers of thiols 11-mercaptopoundecanol and 2-amino-5-mercapto-1,3,4-triazole, on which tetracycline is immobilized protein-containing conjugate, a fixed amount of polyclonal antibodies to tetracyclines is added to the sample and held for 2–3 minutes until formation of an immunocomplex, is introduced into a cell for detection in a phosphate buffer solution with pH 7.1–7.2 and recording a change in the sensor oscillation frequency as a result of interaction of unbound antibodies with a tetracycline-protein conjugate on the surface of sensor electrodes, analytical signal is inversely proportional to the total concentration of tetracyclines in the analysed sample, the concentration is determined from a calibration curve, regeneration of the receptor coating is carried out by applying 0.1 M solution of diethylamine hydrochloride on the surface.

EFFECT: invention provides reduced detection limit of tetracyclines and high sensitivity of detection with high reliability of results, shorter analysis time, wider range of linear determination, and performance of measurements with possibility of regeneration of sensor during 30 measurement cycles.

1 cl, 1 tbl, 8 ex