Quantitation of Heavy Metals by ImmunoassayEPA Grant Number: R824029
Title: Quantitation of Heavy Metals by Immunoassay
Investigators: Blake, Diane A.
Institution: Tulane University of Louisiana
EPA Project Officer: Hiscock, Michael
Project Period: September 1, 1995 through August 31, 1998
Project Amount: $381,920
RFA: Exploratory Research - Chemistry and Physics of Water (1995) RFA Text | Recipients Lists
Research Category: Water , Land and Waste Management , Engineering and Environmental Chemistry
Description:The purpose of this project is to develop immunoassay techniques for the measurement of heavy metal contamination in environmental samples. Immunoassays offer significant advantages over more traditional methods of metal ion analysis; they are quick, inexpensive, simple to perform, and sufficiently portable to be used at the site of contamination. At present, however, immunochemical-based detection of metals is limited by the very small number of antibodies that recognize specific metal ions. Studies during the project period will be directed towards isolation and characterization of monoclonal antibodies that recognize chelated forms of cadmium, copper, lead, and zinc. These antibodies will subsequently be used to construct and optimize immunoassays for specific heavy metals in ambient water and soil samples.
Bifunctional derivatives of metal ion chelators (EDTA, DTPA, DOTA) will be covalently conjugated to proteins and loaded with the desired metal ion. These conjugates will be used to prepare hybridoma cell lines which synthesize metal-specific monoclonal antibodies. The ability of these monoclonal antibodies to recognize specific metals in metal-chelate complexes will be assessed, and those antibodies with appropriate binding properties will be used to construct metal ion immunoassays. In previous EPA-supported studies, our laboratory developed a prototype immunoassay that reliably measured the heavy metal indium at concentrations from 0.005 ppb to 320 ppm (Anal. Biochem. (1994) 217:70-75); similar performance characteristics are expected from new metal ion immunoassays.
Sample analysis is one of the major expenses in the remediation of a contaminated site, and studies have shown that the use of immunoassays can reduce analysis costs by 50% or more, when compared to off-site analysis by more standard techniques. The availability of immunoassays for specific metal ions will lower analysis costs and provide a useful adjunct to more traditional methods of metal analysis.