Methods of use of one step immunochromatographic device for streptococcus a antigen

Abstract

A method to determine the presence or absence of Streptococcus Group A antigen in a sample, comprising the following steps: extracting the antigen from the sample in an assay chamber with two or less extraction reagents, wherein the two reagents may be added to the assay chamber in no particular sequence; introducing a lateral flow immunochromatographic assay device into the extraction reagents containing the extracted antigen without further addition of reagents or manipulation of the sample; forming an antigen-indicator labeling reagent complex; and determining the presence or absence of the antigen in the sample by the presence or absence of a signal formed by the binding of the antigen-indicator labeling reagent complex to an indicator capture reagent specific for said antigen-indicator labeling reagent complex.

Description

BACKGROUND OF THE INVENTION [0001] This invention relates to immunological methods and devices for detecting analytes in biological samples. [0002] Numerous approaches have been developed for detection of a given analyte in a biological sample. Typical of these methods are the so called “lateral flow” and “flow-through” devices and methods. The flow-through device generally uses a porous material with a reagent-containing matrix layered thereon or incorporated therein. Test sample is applied to and flows through the porous material, and analyte in the sample reacts with the reagent(s) to produce a detectable signal on the porous material. These devices are generally encased in a plastic housing or casing with calibrations to aid in the detection of the particular analyte. [0003] Lateral flow assays also utilize a porous membrane for performing analyte detection. Instead of drawing the sample through the membrane perpendicularly, the sample is permitted to flow laterally from an appl...

AI Technical Summary

Benefits of technology

[0077] The control reagent is immobilized to the porous material. Once it binds the control reagent it immobilizes the labeling reagent and prevents it from continuing lateral flow with the liquid sample, giving rise to a positive control signal. Just as the capture reagent is immobilized in a discrete situs on the porous material of the analyte detection region, the control reagent is also imm...

Problems solved by technology

Such tests requiring the addition of more than two reagents introduce the possibility of user error in the sequence of addition of the reagents, necessitating performance of the test by a skilled worker in order to obtain reliable results.

Use of a swab which does not precisely fit into the plastic chamber will result in liquid flow which is too rapid for efficient sample ext...

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