Broad-specificity immunoassay for O,O-diethyl organophosphorus pesticides: application of molecular modeling to improve assay sensitivity and study antibody recognition.
A monoclonal antibody (mAb) against 4-(diethoxyphosphorothioyloxy)benzoic acid (hapten 1) was raised and used to develop a broad-specificity competitive indirect enzyme-linked immunosorbent assay (ciELISA) for 14 O,O-diethyl organophosphorus pesticides (OPs). Computer-assisted molecular modeling was used to model two-dimensional (2D) and three-dimensional (3D) quantitative structure-activity relationships (QSARs) to study antibody recognition. On the basis of insights obtained from the QSAR models, two heterologous coating haptens, 4-(diethoxyphosphorothioylamino)butanoic acid (hapten 2) and 4-(diethoxyphosphorothioyloxy)-2-methylbenzoic acid (hapten 3) were designed, synthesized, and used to develop heterologous ciELISAs with significantly improved sensitivity. The heterologous ciELISA using hapten 2 as the coating hapten showed good sensitivity in a broad-specific manner for eight O,O-diethyl OPs and may be used as a screening method for the determination of these OPs. Our studies demonstrated that molecular modeling can provide insights into the spatial and electronic effects of molecular structures that are important for antibody activity, which can then be used to improve immunoassay sensitivity.
Xu
Zhen-Lin
ZL
Key Laboratory of Food Quality and Safety of Guangdong Province, South China Agricultural University, Guangzhou 510642, China.
Shen
Yu-Dong
YD
Zheng
Wen-Xu
WX
Beier
Ross C
RC
Xie
Gui-Mian
GM
Dong
Jie-Xian
JX
Yang
Jin-Yi
JY
Wang
Hong
H
Lei
Hong-Tao
HT
She
Zhi-Gang
ZG
Sun
Yuan-Ming
YM
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity; D001667:Binding, Competitive; D002417:Cattle; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D006241:Haptens / Q000737:chemistry / Q000276:immunology; D051379:Mice; D008958:Models, Molecular; D008968:Molecular Conformation; D009943:Organophosphorus Compounds / Q000032:analysis* / Q000276:immunology; D010575:Pesticides / Q000032:analysis* / Q000276:immunology; D021281:Quantitative Structure-Activity Relationship
D000911:Antibodies, Monoclonal; D006241:Haptens; D009943:Organophosphorus Compounds; D010575:Pesticides