Pretreatment agent in non-agglutination assays

Abstract

Methods and reagents are disclosed for minimizing a false result in an assay measurement for determining a concentration of an analyte in a sample suspected of containing the analyte. The method comprises pretreating both an antibody and a sample to be subjected to a non-agglutination immunoassay. In the method the antibody and the sample are combined with a pretreatment agent selected from the group consisting of hydroxyphenyl-substituted C1-C5 carboxylic acids and metallic salts thereof and halogen-substituted C1-C5 carboxylic acids and metallic salts thereof in an amount effective to enhance the accuracy of the non-agglutination immunoassay.

What is claimed is: 
     
         1 . A method of pretreating an antibody and a sample to be subjected to a non-agglutination immunoassay, the method comprising combining the antibody and the sample with a pretreatment agent selected from the group consisting of hydroxyphenyl-substituted C1-C5 carboxylic acids and metallic salts thereof and halogen-substituted C1-C5 carboxylic acids and metallic salts thereof in an amount effective to enhance the accuracy of the non-agglutination immunoassay. 
     
     
         2 . The method according to  claim 1  wherein the pretreatment agent is a metallic salt of salicylic acid. 
     
     
         3 . The method according to  claim 1  wherein the pretreatment agent is a metallic salt of a chloro-substituted C1-C5 carboxylic acid. 
     
     
         4 . The method according to  claim 1  wherein the pretreatment agent is a metallic salt of a chloro-substituted acetic acid. 
     
     
         5 . A method of determining analyte in a sample suspected of containing the analyte, the method comprising a non-agglutination immunoassay comprising:
 (a) providing in combination in a medium:
 (i) the sample, 
 (ii) an antibody reagent comprising an antibody for the analyte, and 
 (iii) a pretreatment agent selected from the group consisting of hydroxyphenyl-substituted C1-C5 carboxylic acids and metallic salts thereof and halogen-substituted C1-C5 carboxylic acids and metallic salts thereof in an amount effective to enhance the accuracy of the non-agglutination immunoassay; 
   (b) incubating the medium under conditions for binding of the antibody for the analyte to analyte suspected of being in the sample,   (c) examining the medium for the presence of a complex comprising the analyte and the antibody for the analyte, the presence and/or amount of the complex indicating the presence and/or amount of the analyte in the sample.   
     
     
         6 . The method according to  claim 5  further comprising including in the combination a releasing agent for releasing the analyte from endogenous binding substances. 
     
     
         7 . The method according to  claim 5  wherein the pretreatment agent is a metallic salt of salicylic acid. 
     
     
         8 . The method according to  claim 5  wherein the pretreatment agent is a metallic salt of a chloro-substituted C1-C5 carboxylic acid. 
     
     
         9 . The method according to  claim 5  wherein the pretreatment agent is a metallic salt of a chloro-substituted acetic acid. 
     
     
         10 . The method according to  claim 5  wherein the pretreatment agent is a metallic salt of trichloroacetic acid. 
     
     
         11 . The method according to  claim 5  wherein the antibody reagent further comprises a label. 
     
     
         12 . A method of determining immunosuppressant drug in a sample suspected of containing the immunosuppressant drug, the method comprising a non-agglutination immunoassay comprising:
 (a) providing in combination in a medium:
 (i) the sample, 
 (ii) a releasing agent for releasing the immunosuppressant drug from endogenous binding substances, 
 (iii) an antibody reagent comprising an antibody for the immunosuppressant drug, and 
 (iv) a pretreatment agent selected from the group consisting of hydroxyphenyl-substituted C1-C5 carboxylic acids and metallic salts thereof and halogen-substituted C1-C5 carboxylic acids and metallic salts thereof in an amount effective to enhance the accuracy of the non-agglutination immunoassay; 
   (b) incubating the medium under conditions for binding of the antibody for the immunosuppressant drug to the immunosuppressant drug suspected of being in the sample,   (c) examining the medium for the presence of a complex comprising the immunosuppressant drug and the antibody for the immunosuppressant drug, the presence and/or amount of the complex indicating the presence and/or amount of the immunosuppressant drug in the sample.   
     
     
         13 . The method according to  claim 12  wherein the pretreatment agent is a metallic salt of salicylic acid. 
     
     
         14 . The method according to  claim 12  wherein the pretreatment agent is a metallic salt of a chloro-substituted C1-C5 carboxylic acid. 
     
     
         15 . The method according to  claim 12  wherein the pretreatment agent is a metallic salt of a chloro-substituted acetic acid. 
     
     
         16 . The method according to  claim 12  wherein the pretreatment agent is a metallic salt of trichloroacetic acid. 
     
     
         17 . The method according to  claim 12  wherein the antibody reagent further comprises a label. 
     
     
         18 . The method according to  claim 12  wherein the combination further comprises a particle. 
     
     
         19 . The method according to  claim 12  wherein the antibody reagent further comprises an enzyme label and the combination further comprises a magnetic particle. 
     
     
         20 . The method according to  claim 12  wherein the combination further comprises an analog of the immunosuppressant drug and at least one of the antibody for the immunosuppressant drug or the analog comprises a label.