title: Enzyme immunoassay to determine heavy metals using antibodies to specific metal-EDTA complexes: optimization and validation of an immunoassay for soluble indium.
abstract: An immunoassay that measures soluble indium at concentrations from 0.005 ppb to 320 ppm is described. The assay utilized a monoclonal antibody that binds specifically to indium-EDTA complexes in an antigen-inhibition format. The sensitivity of the assay could be modulated by changing the nature of the soluble inhibiting antigen. The range of the assay was from 0.6 to 320 ppm, 0.1 to 120 ppm, or 0.005 to 2000 ppb when indium-EDTA, indium-(p-nitrobenzyl)-EDTA, or indium-EDTA-bovine serum albumin, respectively was used as the soluble inhibiting antigen. The assay reliably monitored indium concentration in the presence of a 100-fold excess of manganese, magnesium, or copper ions and the quantitation of indium by immunoassay correlated closely with the values obtained using atomic absorption spectroscopy. This technology could be employed in immunoassays for other metals that are priority pollutants.
authors.affiliation: Department of Biochemistry, Meharry Medical College, Nashville, Tennessee 37208.
authors.forename: P
authors.initials: P
authors.lastname: Chakrabarti
authors.forename: F M
authors.initials: FM
authors.lastname: Hatcher
authors.forename: R C
authors.initials: RC
authors.lastname: Blake
authors.forename: P A
authors.initials: PA
authors.lastname: Ladd
authors.forename: D A
authors.initials: DA
authors.lastname: Blake
mesh_terms: D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D004492:Edetic Acid; D007124:Immunoenzyme Techniques; D007074:Immunoglobulin G; D007204:Indium / Q000032:analysis*; D008670:Metals / Q000032:analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013054:Spectrophotometry, Atomic / Q000379:methods
chemical_list: D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D008670:Metals; D007204:Indium; D004492:Edetic Acid