Molybdenum complex & test kit to enhance accuracy of analysis of endogenous analytes in biological fluids

Abstract

Methods for enhancement in accuracy of immunochemical analysis of heterogeneous biological fluids containing exogenous substances that can interfere in immunochemical analysis for endogenous analytes of interest. According to this method a heterogeneous biological fluid sample is pretreated with an interferant suppression effective amount of a molybdenum coordination complex, so as to reduce manifestation of the presence of said exogenous material under immunoassay conditions. This invention is suitable for the suppression of manifestation of exogenous substances, specifically metabolites of drugs of abuse, during the immunoassay of biological fluids of infants for detection of endogenous substances indicative of a wellness or disease state. This invention also has application for similar suppression exogenous substances in the biological fluid of adults that have been inadvertently exposed to such substances (e.g. secondhand smoke).

1 - 13 . (canceled) 
   
   
       14 . A method for reducing the detection of an exogenous substance in a homogeneous assay comprising the steps of:
 A. Obtaining a biological fluid sample comprising an exogenous material or a metabolite of said exogenous material that is believed to be present in said biological fluid sample capable of interfering in analysis of said fluid for said endogenous analyte;   B. Pretreating said biological fluid sample with interferant suppression effective amount of a molybdenum complex, said molybdenum complex formed from molybdate compound and an oxyanion of phosphoric acid and present in said sample at a concentration of from about 5×10 −6  to 5×10 −3  mM; and   C. Subjecting said fluid sample of Step (B) to the homogeneous assay.   
   
   
       15 . The immunoassay of  claim 14 , wherein the molybdenum complex is selected from the group consisting of molybdenyl acidtriphosphate-MoO(H 2 PO 4 ) 3 ; molybdenyl trimetaphosphate-MoO(PO 3 ) 3 ; oxo-μ-oxodi (dihydrogen phosphate) molybdenum-Mo 2 O 3 (H 2 PO 4 ) 4 ; and any combination and mixtures thereof. 
   
   
       16 . The immunoassay of  claim 14 , wherein the molybdenum complex is present in an amount effective to suppress the immunochemical interaction of a exogenous material with an exogenous substance derivative from cocaine. 
   
   
       17 . A kit comprising:
 a molybdenum complex formed from a molybdate compound and an oxyanion of phosphoric acid at a concentration of from about 5×10 −6  to 5×10 −3  mM and capable of interfering with detection of an exogeneous substance in a homogeneous assay.   
   
   
       18 . The kit of  claim 17 , wherein the molybdenum complex is selected from the group consisting of molybdenyl acidtriphosphate-MoO(H 2 PO 4 ) 3 ; molybdenyl trimetaphosphate-MoO(PO 3 ) 3 ; oxo-μ-oxodi (dihydrogen phosphate) molybdenum-Mo 2 O 3 (H 2 PO 4 ) 4 ; and any combination and mixtures thereof.