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.

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.

Abstract: Methods are disclosed of designing antibodies for a sandwich assay for a small molecule having a molecular weight of about 500 to about 2,000. The method comprises preparing a first antibody that binds to the small molecule, and preparing a second antibody that binds to the small molecule at a portion of the small molecule other than a portion to which the first antibody binds. The second antibody is prepared from an immunogen that comprises a predetermined portion of the small molecule. The antibodies may be employed in sandwich assays for the small molecule.

Abstract: Kits containing a chemiluminescent detection system and microfluidics devices and methods for determining the concentration of biotin in a sample are disclosed. The kits, microfluidics devices, and methods utilize a sensitizer capable of generating singlet oxygen in its excited state and having avidin or an analog thereof directly or indirectly bound thereto, as well as a singlet oxygen-activatable chemiluminescent compound having biotin or an analog thereof directly or indirectly bound thereto.

Abstract: Methods are disclosed of designing antibodies for a sandwich assay for a small molecule having a molecular weight of about 500 to about 2,000. The method comprises preparing a first antibody that binds to the small molecule, and preparing a second antibody that binds to the small molecule at a portion of the small molecule other than a portion to which the first antibody binds. The second antibody is prepared from an immunogen that comprises a predetermined portion of the small molecule. The antibodies may be employed in sandwich assays for the small molecule.

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.

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.

Abstract: Methods are disclosed for determining an actual concentration of a hydrophobic haptenic analyte in an unknown sample suspected of containing the hydrophobic haptenic analyte, wherein the unknown sample is suspected of containing an interfering substance. A first assay method is conducted on an unknown sample to obtain a measured concentration of the hydrophobic haptenic analyte in the unknown sample. A second assay method is conducted on the unknown sample to obtain a concentration of the interfering substance in the unknown sample. A predetermined correction formula that utilizes the measured concentration of the hydrophobic haptenic analyte and the measured concentration of the interfering substance obtained in step (a) is applied to determine an actual concentration of the hydrophobic haptenic analyte in the unknown sample.

Abstract: Methods are disclosed of designing antibodies for a sandwich assay for a small molecule having a molecular weight of about 500 to about 2,000. The method comprises preparing a first antibody that binds to the small molecule, and preparing a second antibody that binds to the small molecule at a portion of the small molecule other than a portion to which the first antibody binds. The second antibody is prepared from an immunogen that comprises a predetermined portion of the small molecule. The antibodies may be employed in sandwich assays for the small molecule.

Abstract: Methods are disclosed for determining an actual concentration of a hydrophobic haptenic analyte in an unknown sample suspected of containing the hydrophobic haptenic analyte, wherein the unknown sample is suspected of containing an interfering substance. A first assay method is conducted on an unknown sample to obtain a measured concentration of the hydrophobic haptenic analyte in the unknown sample. A second assay method is conducted on the unknown sample to obtain a concentration of the interfering substance in the unknown sample. A predetermined correction formula that utilizes the measured concentration of the hydrophobic haptenic analyte and the measured concentration of the interfering substance obtained in step (a) is applied to determine an actual concentration of the hydrophobic haptenic analyte in the unknown sample.

Abstract: Methods include determining in a sample an amount of a first isomeric analyte and a second isomeric analyte. A first measurement value and a second measurement value are determined. The first measurement value represents a total amount of the first isomeric analyte and the second isomeric analyte. The second measurement value represents an amount of the second isomeric analyte only. The second measurement value is subtracted from the first measurement value to obtain a resulting value and the resulting value is equated to an amount of the first isomeric analyte in the sample.

Abstract: Methods include determining in a sample an amount of a first isomeric analyte and a second isomeric analyte. A first measurement value and a second measurement value are determined. The first measurement value represents a total amount of the first isomeric analyte and the second isomeric analyte. The second measurement value represents an amount of the second isomeric analyte only. The second measurement value is subtracted from the first measurement value to obtain a resulting value and the resulting value is equated to an amount of the first isomeric analyte in the sample.

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.

Abstract: Compositions are disclosed for releasing an FKBP-binding immunosuppressant drug from endogenous binding substances in a sample suspected of containing the FKBP-binding immunosuppressant drug. The compositions include sirolimus derivatives that are modified with a bulky organic radical in the triene portion of the sirolimus molecule. The compositions may be employed in conjunction with assays for an FKBP-binding immunosuppressant drug in a sample suspected of containing the drug.

Abstract: Methods include adjusting a contribution of one of two analyte homologs to an amount of signal obtained in an assay for determining a total amount of the two analyte homologs in a sample. A non-assay receptor is employed that has a greater binding affinity for whichever of the two analyte homologs whose contribution to the amount of signal is to be adjusted. An amount of the non-assay receptor is sufficient to achieve an adjustment of the contribution of the analyte homolog to the signal. The assay for determining the total amount of the two analyte homologs is conducted where the assay utilizes at least one assay antibody.

Abstract: Methods include determining in a sample an amount of a first isomeric analyte and a second isomeric analyte. A first measurement value and a second measurement value are determined. The first measurement value represents a total amount of the first isomeric analyte and the second isomeric analyte. The second measurement value represents an amount of the second isomeric analyte only. The second measurement value is subtracted from the first measurement value to obtain a resulting value and the resulting value is equated to an amount of the first isomeric analyte in the sample.

Abstract: Methods and reagents are disclosed for detecting 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 measuring assay signal resulting from background only and measuring assay signal resulting from the presence of analyte in the sample plus background and subtracting the first measurement from the second measurement to determine the concentration of analyte in the sample. For example, a measurement result 1 is determined by means of an assay conducted on a portion of the sample where analyte in the sample is substantially sequestered and a measurement result 2 is determined by means of the assay conducted on an equal portion of the same sample where analyte in the sample is substantially non-sequestered. Measurement result 1 is subtracted from measurement result 2 to determine the concentration of analyte in the sample.

Abstract: Compositions are disclosed for releasing an FKBP-binding immunosuppressant drug from endogenous binding substances in a sample suspected of containing the FKBP-binding immunosuppressant drug. The compositions include sirolimus derivatives that are modified with a bulky organic radical in the triene portion of the sirolimus molecule. The compositions may be employed in conjunction with assays for an FKBP-binding immunosuppressant drug in a sample suspected of containing the drug.

Abstract: Methods and reagents are disclosed for detecting 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 measuring assay signal resulting from background only and measuring assay signal resulting from the presence of analyte in the sample plus background and subtracting the first measurement from the second measurement to determine the concentration of analyte in the sample. For example, a measurement result 1 is determined by means of an assay conducted on a portion of the sample where analyte in the sample is substantially sequestered and a measurement result 2 is determined by means of the assay conducted on an equal portion of the same sample where analyte in the sample is substantially non-sequestered. Measurement result 1 is subtracted from measurement result 2 to determine the concentration of analyte in the sample.

Abstract: Methods and reagents are disclosed for pretreating a sample suspected of containing a hydrophobic drug for conducting an assay method for detecting the hydrophobic drug. A combination is provided in a medium that includes the sample, a releasing agent for releasing the hydrophobic drug and the metabolites from endogenous binding moieties, and a selective solubility agent that provides for substantially equal solubility of the hydrophobic drug and the metabolites in the medium. The selective solubility agent includes a water miscible, non-volatile organic solvent and is present in the medium in a concentration sufficient to provide for substantially equal solubility of the hydrophobic drug and the metabolites in the medium. The medium, which may further include a hemolytic agent, is incubated under conditions for releasing the hydrophobic drug and the metabolites from endogenous binding moieties. The pretreated sample may be subjected to an assay for determining the hydrophobic drug.