Rapid bioassay of organophosphates and carbamate residues

    A bioassay technique was developed at TARI for the rapid detection of pesticide residues, organophosphates and carbamates on agricultural produce. The technique was based on the theory that the insecticide organophosphates (OPs) and carbamates (Carbs) can block the action of the enzyme acetylcholinesterase (AChE), in this case extracted from houseflies. If the sample contains pesticide residues, OPs or Carbs, the housefly AChE is unable to successfully break down the color-indicator matrix (containing Acetylthiocholine iodine and 5,5´-Dithiobis(2-nitrobenzoic acid)).

Reagents (left) and instruments (right) for testing organophosphate and carbamate residues on agricultural produce.

Results of testing agricultural produce for pesticide residues, organophosphates and carbamates.

Detection of pyrethroid insecticides by immunoassays

    A competitive ELISA test was developed for the detection of pyrethroid insecticides. The antibody used in the ELISA test was isolated from animals immunized with pyrethroid hapten conjugates.

Procedure for detection of pyrethroid insecticides: a). sample extraction and b). ELISA test for pyrethroid insecticides.