Home Diagnostics, Inc.

Patrick J Carroll

Douglas E Bell

Jon Schneider

Robin A Wiscovitch

An improved multi-layered diagnostic sanitary test strip for receiving a heterogenous fluid, such as whole blood, to test for presence and/or amount of a suspected analyte in the fluid by facilitating a color change in the strip corresponding to the amount of the analyte in the fluid, wherein the test strip includes fluid volume control dams to prevent spillage of the fluid from the strip and a chemical reagent solution that facilitates end-point testing. The improved test strip comprises no more than two operative layers and: (a) a reaction membrane containing a reagent capable of reacting with the analyte of interest to produce a measurable change in said membrane; (b) an upper support layer defining a sample receiving port for receiving the fluid sample thereat; (c) one or more structures for directing the sample containing the analyte of interest through at least a portion of said reaction membrane; and (d) a lower support layer having a reaction viewing port in vertical alignment with said membrane for displaying said measurable change, said lower support being associated with said upper support to secure said reaction membrane in said test strip.

Diagnostic sanitary test strip

An improved multi-layered diagnostic sanitary test strip for receiving a heterogenous fluid, such as whole blood, to test for presence and/or amount of a suspected analyte in the fluid by facilitating a color change in the strip corresponding to the amount of the analyte in the fluid, wherein the test strip includes fluid volume control dams to prevent spillage of the fluid from the strip and a chemical reagent solution that facilitates end-point testing. The improved test strip comprises (a) an upper support strip having a fluid receiving port and (b) a lower support strip having a color change viewing port and securely sandwiched therebetween (c) a spreading mesh screen for uniformly distributing the fluid, (d) a chemically treated separating layer for removing an undesirable element, e.g. red blood cells, from the fluid received from the mesh screen, (e) an isotropic membrane chemically treated with a reagent indicator solution for removing any remaining portions of the undesirable element, producing a color change proportionate to the amount of the suspected analyte in the fluid and facilitating an end-point ramp test, and (f) volume control dam partitions for retaining fluid on and in the strip.

Disclosed is a multi-layered test strip device for receiving whole blood on which a test for a suspected analyte is performed. The test confirms the presence, absence, or the amount of analyte, if present. The multi-layered device comprises two outside support layers between which are, in descending order relative to the horizontal plane, a) a spreading screen having defined characteristics, b) a separating layer which removes red blood cells at least partially via a red blood cell binding agent, and c) a membrane reagent layer; wherein the screen and each layer is in close and contiguous contact with the layer which follows it, and wherein at least one of layers a), b), and c) is conditioned by a pre-treatment. The screen can have openings of from 10-200 microns. The blood cell binding agents are antibodies to red blood cells, chemical agents, or lectins. The separating layer has screen opening of preferably 20-200 microns.

Growing community of inventors

Ft. Lauderdale, FL, United States of America

Patrick J Carroll