Development of enzyme immunoassay for detection of DDT.
Dichlorodiphenyltrichloroethane (DDT) is one of the persistent organic pollutants (POPs) widely found in the environment and in the general population. In this study, a direct competitive enzyme immunoassay (EIA) has been developed for the quantitative analysis of DDT. To generate a specific polyclonal antibody for EIA, p, p'-DDT was conjugated to porcine thyroglobulin for rabbit immunization. At optimized EIA conditions, the standard curves ranged from 0.137 to 100 ng/mL with the quantification limit of 0.41 ng/mL. The coefficients of variation (CV%) were 5.42-10.53% for intra-assay and 6.04-7.26% for inter-assay. Cross-reactivities with DDT metabolites (DDTs, including o, p'-DDT, p, p'-DDD, o, p'-DDD, p, p'-DDE, o, p'-DDE, p, p'-dichlorobenzophenone (DCBP), o, p'-DCBP) were investigated. The polyclonal antibody showed relatively low and/or no cross-reactivity with these compounds, and the assay was seen to be highly selective for p, p'-DDT. Moreover, the DDTs could be ranked by their reactivity: DDT > DDD > DDE > DCBP. In addition, the characterization of the polyclonal antibody indicated that the antiserum possesses a high specificity for p, p'-isomers. The results indicated that the developed EIA using this antibody could be a convenient and supplemental analytical tool for monitoring DDT.
Hirano
Masashi
M
Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, 3-1-100 Tsukide, Kumamoto, Japan.
Kitamura
Kazuyuki
K
Kato
Ikuo
I
Yanaihara
Chizuko
C
Iwamoto
Ken-ichi
K
Sekiyama
Makiko
M
Watanabe
Chiho
C
Nakamoto
Takashi
T
Miyamoto
Nobukazu
N
Onishi
Yuta
Y
Arizono
Koji
K
D000818:Animals; D000906:Antibodies / Q000276:immunology; D000918:Antibody Specificity; D002347:Carps / Q000378:metabolism; D003429:Cross Reactions; D003634:DDT / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods*; D004787:Environmental Pollution / Q000032:analysis*; D007124:Immunoenzyme Techniques / Q000379:methods / Q000592:standards; D007536:Isomerism; D010573:Pesticide Residues / Q000032:analysis*; D010575:Pesticides / Q000032:analysis*; D011817:Rabbits; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012989:Soil Pollutants / Q000032:analysis
D000906:Antibodies; D010573:Pesticide Residues; D010575:Pesticides; D012989:Soil Pollutants; D003634:DDT