Hapten-antibody recognition studies in competitive immunoassay of α-zearalanol analogs by computational chemistry and Pearson Correlation analysis

The molecular recognition of hapten-antibody is a fundamental event in competitive immunoassay, which guarantees the sensitivity and specificity of immunoassay for the detection of haptens. The aim of this study is to investigate the correlation between binding ability of one monoclonal antibody, 1H9B4, recognizing and the molecular aspects of alpha-zearalanol analogs. The mouse-derived monoclonal antibody was produced by using alpha-zearalanol conjugated to bovine serum albumin as an immunogen. The antibody recognition abilities, expressed as IC50 values, were determined by a competitive ELISA. All of the hapten molecules were optimized by Density Function Theory (DFT) at B3LYP/6-31G* level and the conformation and electrostatic molecular isosurface were employed to explain the molecular recognition between alpha-zearalanol analogs and antibody 1H9B4. Pearson Correlation analysis between molecular descriptors and IC50 values was qualitatively undertaken and the results showed that one molecular descriptor, surface of the hapten molecule, clearly demonstrated linear relationship with antibody recognition ability, where the relationship coefficient was 0.88 and the correlation was significant at p < 0.05 level. The study shows that computational chemistry and Pearson Correlation analysis can be used as tool to help the immunochemistries better understand the processing of antibody recognition of hapten molecules in competitive immunoassay. Copyright (C) 2011 John Wiley & Sons, Ltd.