Molecularly imprinted sensor based on an enzyme amplifier for ultratrace oxytetracycline determination.

A novel strategy for preparing highly sensitive, molecularly imprinted sensors based on enzyme amplifiers was proposed for oxytetracycline (OTC) determination. A molecularly imprinted polymer (MIP) film was used as an artificial antibody to interact with OTC and horseradish peroxidase-labeled OTC (HRP-OTC). Oxytetracycline was determined according to the competition reaction. The molecularly imprinted sensor was characterized by alternating current (ac) impedance spectroscopy, differential pulse voltammetry (DPV), and cyclic voltammetry (CV). The DPV technique was performed to verify the voltammetric behavior of the molecularly imprinted sensor. At the concentration of 0-1 x 10(-7) mol/L, OTC could be determined with a detection limit of 6.49 x 10(-10) mol/L. The MIP artificial immunosensor showed high sensitivity, selectivity, and reproducibility. Determination of OTC in samples showed good recovery.