Detection of environmentally hazardous pesticide in fruit and vegetable samples using gold nanoparticles

•Biosynthesized AuNPs were characterized by spectroscopically and microscopically.•Detection of pesticide by bio-conjugated AuNPs from fruits and vegetables.•Dipstick immunoassay and ELISA were developed to detect pesticide (kitazine).

A new approach for simple, competitive and sensitive, dipstick immunoassay (DIA) was developed to detect organophosphorus pesticide. Residual pesticides such as kitazine in fruits and vegetables are one of the major food safety concerns for consumers in the world. It is the alternative method to nitrocellulose strip (NC) for the detection of harmful pesticides. The matrix effects of different food samples (tomato, cucumber, grapes and orange) were studied in flow through ELISA (Enzyme Linked Immunoassay) and DIA method. Different size morphology was synthesized from gold nanoparticles and bioconjugated to Ig G, which served as the detecting agent confirmed by AFM. The different concentration of organophosphorus in the food sample was detected by the development of purple color in the membrane strips. Among four fruit juices, the grape juice exhibits increased absorbance resulted that the bioconjugated gold nanoparticle is actively detected the kitazine present in the grape juice evidenced by ELISA method has good reproducibility and satisfactory accuracy. The interpretation of the results was visual, and these ELISAs can be used as convenient qualitative tools for the rapid screening ofkitazine residues in food samples.