Production of a specific monoclonal antibody against mercury-chelate complexes and its application in antibody-based assays

In this study, monoclonal antibodies (mAbs) against the chelated Hg2 + were prepared. The immunoconjugate (chelated Hg2 +, or KLH-ITCBE-Hg2 +), was generated by coupling of Hg2 + to keyhole limpet hemocyanin (KLH) with a bifunctional chelator 1-(4-isothiocyanobenzyl)- ethylenediamine N, N, N’, N’-tetraacetic acid (ITCBE). Five hybridoma cell lines secreting antibodies that specifically reacted with bovine serum albumin (BSA)-glutathione-Hg2+, but not with BSA-glutathione, were isolated from the fusion between the spleen cells of a mouse immunised with KLH-ITCBE-Hg2+ and SP2/0 myeloma cells. A clone, B/B11, was chosen for further development of a specific and rapid immunoassay for Hg2 +. In this context, we established an effective competitive indirect enzyme-linked immunosorbent assay (ELISA) based on the mAb for Hg2 +. The assay is specific to mercury with an IC50 value of 1.589 µM and the lowest detection limit of 0.009 µM. The immunoassay was applied for detection and measurement of mercury in various water samples and in greengrocery samples. The recoveries from ultrapure water, tap water, and pool water were in the range of 94.38–109.67%, and in greengrocery samples were from 85.12 to 92.68%. Overall, the optimised ELISA based on mAbs is a convenient and efficient analytical tool for monitoring mercury residues in water and in the greengrocery samples.