Selective and sensitive determination of ochratoxin A based on a molecularly imprinted electrochemical luminescence sensor

Abstract

This paper reports a new molecularly imprinted electrochemical luminescence (MIP-ECL) sensor for the determination of ochratoxin A (OTA) with high selectivity and sensitivity. Ru(bpy)₃²⁺ was immobilized on the electrode surface as the luminescent material by using Nafion. The process of template elution and rebinding acted as a gate to control the flux of probes, which passed through the cavities and reacted on the electrode surface. When the imprinted film was rebound with OTA, the ECL signal decreased. Under optimal conditions, the MIP-ECL sensor showed a wide linear range from 0.1 ng mL⁻¹ to 10 ng mL⁻¹ with a detection limit (S/N = 3) of 0.03 ng mL⁻¹. Corn samples were assayed by using this sensor, and recoveries ranging from 95.2% to 102.7% were obtained.