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.

1 .- 11 . (canceled) 
     
     
         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, wherein the releasing agent is selected from the group consisting of one or more of a structural analog of the immunosuppressant drug and a hemolytic agent, 
 (iii) an antibody reagent comprising an antibody for the immunosuppressant drug, 
 (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, wherein the incubation temperature is 5 degrees C. to 99 degrees C. and the time period for the incubation is 0.2 seconds to 24 hours,   (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,   
       wherein the immunosuppressant drug is selected from the group consisting of cyclosporine, everolimus, siroliumus and tacrolimus. 
     
     
         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 structural analog of the immunosuppressant drug and at least one of the antibody for the immunosuppressant drug or the analog comprises a label. 
     
     
         21 . The method according to  claim 12 , wherein the releasing agent further comprises a solubility agent.