direct competitive biomimetic immunoassay based on quantum dot label for simultaneous determination of two pesticide residues in fruit and vegetable samples

In this study, trichlorfon and chlorpyrifos conjugated to cdse/zns quantum dots with different emission wavelengths were adopted as labels. a hydrophilic imprinted film synthesized directly on the surface of a 96-well plate was used as the antibody. a direct competitive biomimetic immunoassay method for simultaneous determination of trichlorfon and chlorpyrifos in fruits and vegetables was developed. under optimal conditions, the limit of detection of this method was 18.0 μg/l for chlorpyrifos (55 mg/kg for sample) and 19.0 μg/l for trichlorfon (45 mg/kg for sample). orange and carrot samples spiked with chlorpyrifos and trichlorfon were extracted and determined by this method with recoveries ranging from 77.8 to 92.0%. the method was applied for detection of chlorpyrifos and trichlorfon residues in banana and apple samples, and the results correlated well with those obtained using gas chromatography.