Enzyme-Linked Immunosorbent Assay for the Pyrethroid Deltamethrin

Abstract

A competitive enzyme-linked immunosorbent assay (ELISA) for the detection of deltamethrin was developed. Two haptens, cyano[3-(4-aminophenoxy)phenyl]methyl 1R-cis-3-(2,2-dibromoethenyl)-2,2-dimethylcyclopropanecarboxylate and 3-[(+/-)-cyano[1R-cis-3-(2,2-dibromoethenyl)-2,2-dimethylcyclopropan ecarbonyloxy]methyl]phenoxyacetic acid, were synthesized and conjugated with thyroglobulin as immunogens. Four antisera were generated and screened against six different coating antigens. The assay that was the most sensitive for deltamethrin was optimized and characterized. The I(50) for deltamethrin was 17.5 +/- 3.6 microg/L, and the lower detection limit was 1.1 +/- 0.5 microg/L. This ELISA assay had relatively low cross-reactivities with other major pyrethroids, such as permethrin, phenothrin, bioresmethrin, cyfluthrin, and cypermethrin. Methanol was found to be the best organic cosolvent for this ELISA, with optimal sensitivity observed at a concentration of 40% (v/v). The assay parameters were unchanged at pH values between 5.0 and 8.0, whereas higher ionic strengths strongly suppressed the absorbances. To increase the sensitivity of the overall method, a C(18) sorbent-based solid-phase extraction was used for river water samples. River water samples fortified with deltamethrin were analyzed according to this method. Good recoveries and correlation with spike levels were observed.

Simultaneous determination of permethrin and deltamethrin in water samples by magnetic solid-phase extraction coupled with dispersive liquid-liquid microextraction combined with gas chromatography

“…In addition, it can be used in the large volumes of sample in contrast to the DLLME method. The recovery of RESEARCH ARTICLE the proposed method are comparable with other extraction methods [59][60][61] . Finally, the proposed method has exciting potential to determine the selected analytes at trace levels in water samples.…”

“…The quantitative results of the proposed method are better than those of homogeneous liquid-liquid microextraction via flotation assistance (HLLME-FA), 59 or micro liquid-liquid extraction. 60 Comparison of the proposed method with micro liquid-liquid extraction and competitive enzyme-linked immunosorbent assays (C-ELISAs) 61 for the extraction and determination of the analytes indicates that this novel method has a short extraction time for determination of the analytes. C-ELISAs is expensive and requires more organic solvents and time.…”

“…Table 2 Relative standard deviation at three different concentration levels by using proposed method. 61 MSPE-DLLME-GC-FID 1.0-1.5 0.5-100 0.01 1 88-95…”

Syntheses of haptens and hapten-protein conjugates for insecticide propoxur and cyhalothrin

“…Therefore, a generic method for hapten designing was to have an amino group at the aromatic moiety of the cyhalothrin molecule for coupling with protein, and this method was applied to the synthesis of haptens for the development of ELISA of several pyrethroid insecticides [17][18][19]. However, this method requires a synthetic route involving four steps including chlorination and cyanidation.…”

Fabrication of Non-woven Fabric-Based SERS Substrate for Direct Detection of Pesticide Residues in Fruits

“…The problems of pesticide residues on fruits and vegetables have also been paid more attention due to the wide use of pesticide. Various conventional methods, such as mass spectrometry, capillary electrophoresis and chromatography, have been applied for the detection of trace level of pesticide residues [3][4][5][6][7][8]. However, these methods are usually time-consuming requiring for complicated pre-treatments and must be carried out in laboratory with the expensive instruments.…”