Development of Fluorescence Polarization Immunoassay for the Rapid Detection of 6-Chloronicotinic Acid: Main Metabolite of Neonicotinoid Insecticides

Abstract

A fluorescence polarization immunoassay (FPIA) for the quantitative determination of 6-chloronicotinic acid (6-CNA) using polyclonal antibody was developed. The 6-CNA-protein (bovine serum albumin and soybean trypsin inhibitor) conjugates and fluorescein-labeled 6-CNA derivative (tracer) were prepared and used as the immunogens and tracer, respectively. The synthesized tracer was purified by thin layer chromatography (TLC) and showed a good binding to antiserum (73/5) which was obtained from the immunized rabbit (No. 73) with 6-CNA-BSA conjugate. The detection limit (10% inhibition) of FPIA was 4 microg/mL, and IC(50) value was 32 microg/mL. The FPIA showed a cross-reaction for 5-amino-2-chloropyridine (60%), but no cross-reaction for other pesticides was observed. Recoveries for spiked apple, urine, soil, and water samples (5, 50, and 500 ppm) averaging between 78.6 +/- 8.8 and 114 +/- 18% were reasonable and in good agreement with the amounts spiked. Although the developed FPIA possesses low sensitivity, this assay is more simple and quick than other analytical methods, such as high performance liquid chromatography and gas chromatography. Thus, the developed FPIA method could be a useful tool for express screening 6-CNA in agricultural, environmental, and biological samples.

Fluorescence polarization as a tool for the detection of a widely used herbicide, butachlor, in polluted waters

“…Pesticides are sometimes detected in the presence of organic solvents that were used for extraction of sample matrices or improving the solubility in immunoassays. 12,15 Therefore, four organic solvents, methanol, acetone, acetonitrile and DMF, were used to evaluate the solvent tolerance in the present study. Observed effects were dependent on solvent type and concentration (Fig.…”

“…9,10 Fluorescence polarization immunoassay (FPIA) is a homogeneous technique that meets the requirements of a simple, reliable, fast and cost-effective analysis. [9][10][11][12][13][14] Recently, the use of FPIA for the determination of pesticides and veterinary drugs, [14][15][16] and toxins 9,17 in agricultural products and environmental samples has been reported. ELISA and membrane immunoassay for the herbicide butachlor have also been reported by Dzantiev et al and Yakovleva et al 2,18 However, to the best of our knowledge, no FPIA research on the analysis of butachlor has been published to date.…”

Heterologous strategy enhancing the sensitivity of the fluorescence polarization immunoassay of clinafloxacin in goat milk

“…It seems that the high CR from ciprofloxacin is usually inevitable in the immunoassay of FQ drugs, but a statutory confirmatory method is usually still needed to exclude the false positive after a screening assay . For a rapid screening purpose, the FPIA with low CR is acceptable considering the speed and convenience of an FPIA …”

Fluorescence polarization immunoassay for highly efficient detection of clothianidin in agricultural samples

“…Nowadays, FPIA has been widely applied to detect various analytes, which contaminate food and the environment such as drugs and related materials. [17][18][19] Recently, ELISAs for detecting clothianidin have been reported. 5,20 The present work aims to develop a rapid and sensitive FPIA for the determination of clothianidin and evaluate the analytical reliability using agricultural samples (Fig.…”