Hygeia Sciences, Inc.

Btc Diagnostics Limited Partnership

Izak Bahar

Francis X Cole

Wendy Jones

L Edward Cannon

Walter D Cantarow

Elliott Block

Mary Coseo

Eric C Sigillo

Nancy J Cicia

Bego Gerber

Frank Cole

Patricia Kovac

Cheryl A Eaton

Cheryl Eaton

John Bruins

A simultaneous dual analyte assay for determining the fertile period of the human menstrual cycle. The assay utilizes a capture reaction component consisting of P-3-G immobilized on a microporous membrane, a blocking reaction component consisting of anti E.sub.1 -3-G antibody, a labelled reaction component consisting of gold particle labelled anti E.sub.1 -3-G antibody, and an ambifunctional reaction component consisting of a hybrid immunoreactive substance having an anti P-3-G antibody binding site and a plurality of E.sub.1 -3-G determinant binding sites. An aqueous sample containing P-3-G and E.sub.1 -3-G is contacted with the components and the assay is calibrated to provide a positive assay result only when the concentration of P-3-G in the sample is less than a predetermined concentration and the concentration of E.sub.1 -3-G in the sample is more than a preselected concentration whereby a visually inspectable quantity of an immunocomposite is produced that consists of both the P-3-G immobilized on the microporous membrane and the gold labelled anti E.sub.1 -3-G antibody.

Simultaneous dual analyte assay

An assay procedure that is particularly valuable for detecting and/or determining the presence of threshold levels of analyte ligands in biological fluids. In one particularized and specialized aspect the disclosure is directed to procedures for detecting and/or determining threshold levels of hormone metabolites such as pregnanediol-3-glucuronide (P.sub.3 G) and estrone-3-glucuronide (E.sub.1 3G) in human urine. The assay consists of contacting a sample containing the analyte with a known amount of an antibody thereto and with a calibrated amount of the analyte itself that is conjugated to said solid support. When the level of the analyte in the sample exceeds a threshold level, such as 5 ug/ml for P.sub.3 G, the antibody will be insufficient to block all of the corresponding analyte on the solid support. Thus, upon addition of labelled antibody to the assay system, a detectable immunoreaction product becomes attached to the support to indicate that the amount of analyte in the sample exceeds the threshold level. On the other hand, if the level of the analyte in the sample is below the threshold amount, the free antibody will be sufficient to block all of the corresponding analyte on the solid support preventing labelled antibody from forming a detectable immunoreaction product on the support and thus no signal will appear.

Positive step immunoassay

Detection of bindable substances such as antibodies and antigens using enzyme linked immunosorbent assays having particular utility in home diagnostic applications. The preferred implementation of the invention is characterized by the steps of admixing a sample suspected of containing the bindable substance to be detected with an antibody-enzyme conjugate, immersing an antibody coated solid support into the mixture and then exposing the coated support to an activated chromogenic solution. The conjugate for use in the home diagnostic assay is preferably contained within a lyophilized mixture. The lyophilized mixture contains components which preserve the antibody-conjugate's reactivity and immunologic binding specificity even if the lyophilized mixture had been subjected to hot, humid environmental conditions. Active components in the lyophilized mixture include polyethylene glycol, sugars, and surfactant. The antibody coated support is treated with an improved blocking solution containing a blocking agent such as bovine serum albumin or milk protein in admixture with a sugar. The blocking solution prevents nonspecific binding of immunologic reagents to the support and protects the antibody on the support from loss of reactivity and immunologic binding specificity even if the antibody coated support had been subjected to hot, humid environmental conditions.

Enzyme immunoassays and immunologic reagents

An assay employing two antibodies. A microporous carrier supports a plurality of layers, in which conjugates form between test antigens and antibodies. Quantitative results are obtained from an immobilized antibody within an indicating substrate.

Multiple-antibody detection of antigen

Colorimetric detection of bindable substances such as antibodies and antigens using chromogens of improved sensitivity and stability. The chromogens take the form of activated solutions containing tetramethylbenzidine or water soluble derivatives of tetramethylbenzidine. Such chromogens are of particular use in home testing applications for detection of antigens such as human chorionic gonadotropin, human luteinizing hormone, and gonococcus bacteria, as well as the detection of antibodies for these substances.

Enzyme immunoassay with two-part solution of tetramethylbenzidine as

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Chestnut Hill, MA, United States of America

Izak Bahar