Development of a Chemiluminescent Enzyme Immunoassay for Detection of Triazophos in Agricultural Products

A chemiluminescent enzyme immunoassay(CLEIA) method for the detection of triazophos pesticide residue in agricultural products was developed.Checkerboard method was used to get the working concentrations of the immunoassay.Based on the experiment,the concentration of antibody was selected as 2.0 μg /mL,and the concentration of enzyme labeled hapten was chosen as 0.006μg/mL.Chemiluminescent enhanced solution(CES) was optimized by L25(56) orthogonal experiment and the optimized conditions for the CES were as follows:percentage of organic solvent(DMF)in the CES:6.4%,buffer:0.01 mmol /L Tris- HCl(pH 9.0),concentration of luminol:0.6mmol /L,concentration of H2O2:2 mmol/L,and concentration of 4-IMP:1 mmol/L.The sensitivity for detection was 0.489 ng /mL at a practical working concentration range of 0.16- 20.00 ng /mL.The recoveries of triazophos in apple,zucchini,rice,orange,litchi and cabbage samples were in the range of 82.8%- 118.4%.The confirmation experiment showed that the analytical result of CLEIA method was in agreement with that of the GC- MS method.The developed CLEIA method could be employed in the screening of triazophos residue in apple,zucchini,rice and other samples.