Auric Enterprises, LLC

Bioassay Works

Calypte Biomedical Corporation

Leslie Kirkegaard

Glen Ford

A chromatographic specific binding assay strip device, comprising: a non-permeable platform strip; a permeable membrane testing strip positioned on top of said non-permeable platform strip, with the testing strip comprising at least one capture reagent site containing a capture reagent for at least one specific analyte, a sample receiving pad positioned on top of and at a proximal end of the non-permeable platform strip, with the sample receiving pad having contact with a proximal end of said permeable membrane testing strip, a reservoir pad positioned on top of and at a distal end of said non-permeable membrane testing strip, with the reservoir pad having contact with a proximal end of said permeable membrane test strip; a supporting strip attached to and extending from the proximal end of said non-permeable platform strip; and a conjugate pad positioned on said supporting strip, said conjugate pad comprising a semi-permeable membrane containing a colorant conjugate. The semi-permeable membrane acts as a barrier between the conjugate pad and the sample receiving pad, regulating the flow through the semi-permeable membrane and overall flow of the assay. By dipping the conjugate pad into a sample solution, there will be increased binding between the analyte in the sample and the conjugate (preferably colloidal gold), thereby giving improved results on the lateral flow assay.

Immuno gold lateral flow assay

A chromatographic specific binding assay strip device, comprising: a non-permeable platform strip; a permeable membrane testing strip positioned on top of said non-permeable platform strip, with the testing strip comprising at least one capture reagent site containing a capture reagent for at least one specific analyte, a sample receiving pad positioned on top of and at a proximal end of the non-permeable platform strip, with the sample receiving pad having contact with a proximal end of said permeable membrane testing strip, a reservoir pad positioned on top of and at a distal end of said non-permeable membrane testing strip, with the reservoir pad having contact with a proximal end of said permeable membrane test strip; a supporting strip attached to and extending from the proximal end of said non-permeable platform strip; and a conjugate pad positioned on said supporting strip, said conjugate pad comprising a semi-permeable membrane containing a colorant conjugate. The semi-permeable membrane acts as a barrier between the conjugate pad and the sample receiving pad, regulating the flow through the semi-permeable membrane and overall flow of the assay by dipping the conjugate pad into a sample solution, there will be increased binding between the analyte in the sample and the conjugate (preferably colloidal gold), thereby giving improved results on the lateral flow assay.

The present invention comprises novel 'one-step' methods for the production of gold sol and gold sol conjugates. The methods disclosed herein produce gold sol and colloidal gold conjugates with product with yields on the order of about 20 ODs. Since current methods in the art yield conjugates at concentrations on the order of about 2 ODs, the present invention represents an approximately 10-fold increase in production over conventional methods. The novel method provided herein also does not result in the production of undesired aggregate by-products that, in conventional methods, must be removed via centrifugation, filtration or other means. The new method is therefore less labor intensive and requires less time to complete than standard methods in the art for synthesizing pure colloidal gold conjugates.

One-step production of gold sols

A chromatographic lateral-flow assay system for rapid, high sensitivity method of detecting low levels of ligands in body fluids, with few false positives and few false negatives. The lateral-flow assay may have a membrane strip in ribbon form, which increases detection on the order of 2 to 10 fold over the conventional chromatographic specific binding assay techniques by placing a dried or lyophilized conjugate in colloidal spheres opposite side of the lateral flow membrane strip. A chromatographic specific binding assay strip device, comprising: a laminate strip having a first side and an opposite second side; a conjugate pad or membrane disposed on said first side of said laminate; a sample receiving pad or membrane strip and reservoir pad or membrane disposed on said second side of said laminate; and a detection pad or membrane strip disposed between the sample pad or membrane and the reservoir pad or membrane on said second side of said laminate. The assay system comprises a housing device, such as a test tube or cassettes to facilitate the mixing of a sample solution with the dried or lyophilized conjugate, and kits.

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Ijamsville, MD, United States of America

Leslie Kirkegaard