Abstract: Disclosed is an assay device which comprises a liquid sample addition zone, a reagent zone, a detection zone, and a wicking zone, all defining a fluid flow path. The device further comprises a reagent addition zone along and in fluid communication with the fluid flow path downstream of the sample addition zone and upstream of the detection zone. An interrupting wash is added at this reagent addition zone in accordance with the method of the subject invention to control sample volume. The interrupting wash fluid is added at a predetermined fill volume on the chip device and also serves to wash the detection channel and fill the remaining chip volume.

Abstract: Described herein are clinical diagnostics and more specifically to a lateral-flow assay devices.

Abstract: Disclosed is method of improving flow of a liquid sample in an assay device, as well as a method of performing an assay on a liquid sample for the detection of one or more analytes of interest. The methods use the addition of a reagent, such as a wash reagent, to wet the fluid flow path of a sample prior to sample addition, thereby improving flow of the sample through the fluid flow path that has been wetted as opposed to flow of the sample through the fluid flow path that has not been wetted. The reagent wets the fluid flow path between the sample addition zone and the wicking zone.

Abstract: A lateral-flow assay device includes a substrate with a sample addition zone and a fluid flow path. A cover supports a filter having a portion contacting the substrate to create a contact area that at least partly overlaps the sample addition zone. Another portion extends from the contact portion to the supported periphery of the filter to define with the substrate a reservoir configured to retain the filtrate by capillary pressure between the substrate and the extending portion. The reservoir volume is based on an acute angle formed between the substrate and the extending portion of the filter and on a fluid meniscus of the filtrate. The filter and sample addition zone are configured to provide capillary pressure drawing the filtrate from the reservoir to the sample addition zone. Methods for controlling flow characteristics in a lateral-flow assay device are also described.

Abstract: Disclosed is method of improving flow of a liquid sample in an assay device, as well as a method of performing an assay on a liquid sample for the detection of one or more analytes of interest. The methods use the addition of a reagent, such as a wash reagent, to wet the fluid flow path of a sample prior to sample addition, thereby improving flow of the sample through the fluid flow path that has been wetted as opposed to flow of the sample through the fluid flow path that has not been wetted. The reagent wets the fluid flow path between the sample addition zone and the wicking zone.

Abstract: Disclosed is an assay device which comprises a liquid sample addition zone, a reagent zone, a detection zone, and a wicking zone, all defining a fluid flow path. The device further comprises a reagent addition zone along and in fluid communication with the fluid flow path downstream of the sample addition zone and upstream of the detection zone. An interrupting wash is added at this reagent addition zone in accordance with the method of the subject invention to control sample volume. The interrupting wash fluid is added at a predetermined fill volume on the chip device and also serves to wash the detection channel and fill the remaining chip volume.

Abstract: Disclosed is an assay device which comprises a liquid sample addition zone, a reagent zone, a detection zone, and a wicking zone, all defining a fluid flow path. The device further comprises a reagent addition zone along and in fluid communication with the fluid flow path downstream of the sample addition zone and upstream of the detection zone. An interrupting wash is added at this reagent addition zone in accordance with the method of the subject invention to control sample volume. The interrupting wash fluid is added at a predetermined fill volume on the chip device and also serves to wash the detection channel and fill the remaining chip volume.

Abstract: An assay device includes: a detection zone which includes a first set of projections which are capable of generating capillary flow. A wicking zone (WZ) has a capacity to receive liquid sample flowing from the detection zone and includes a second set of projections which are capable of generating capillary flow. The WZ is rectangular in shape and the longer side of the rectangle extends in the direction of flow to thereby reduce the pressure gradient in the assay device which increases the total flow time of liquid sample compared to a WZ having equal length sides and same volume. At least a portion of the second set of projections have at least one dimension selected from a diameter, a center-to-center spacing, or a gap between projections that is different from the first set of projections, and is selected to increase the total flow time of the sample.

Abstract: Disclosed is method of improving flow of a liquid sample in an assay device, as well as a method of performing an assay on a liquid sample for the detection of one or more analytes of interest. The methods use the addition of a reagent, such as a wash reagent, to wet the fluid flow path of a sample prior to sample addition, thereby improving flow of the sample through the fluid flow path that has been wetted as opposed to flow of the sample through the fluid flow path that has not been wetted. The reagent wets the fluid flow path between the sample addition zone and the wicking zone.

Abstract: An assay device includes: a liquid sample zone; a reagent zone downstream and in fluid communication with the sample zone containing a reagent material; a detection zone in fluid communication with the reagent zone having capture elements bound thereto; and a wicking zone in fluid communication with the capture zone having a capacity to receive liquid sample flowing from the detection zone. The sample receiving zone, the reagent zone, the detection zone and the wicking zone define a fluid flow path and at least a part of the fluid flow path has a substrate and projections which extend substantially vertically from the substrate, wherein the projections have a height, cross-section and a distance between one another that defines a space between the projections capable of generating capillary flow parallel to the substrate surface. In addition, the fluid flow path having projections includes a corner section which changes the direction of the flow path.

Abstract: An assay device includes: a detection zone which includes a first set of projections which are capable of generating capillary flow. A wicking zone (WZ) has a capacity to receive liquid sample flowing from the detection zone and includes a second set of projections which are capable of generating capillary flow. The WZ is rectangular in shape and the longer side of the rectangle extends in the direction of flow to thereby reduce the pressure gradient in the assay device which increases the total flow time of liquid sample compared to a WZ having equal length sides and same volume. At least a portion of the second set of projections have at least one dimension selected from a diameter, a center-to-center spacing, or a gap between projections that is different from the first set of projections, and is selected to increase the total flow time of the sample.

Abstract: A lateral-flow assay device includes a substrate with a sample addition zone and a fluid flow path. A cover supports a filter having a portion contacting the substrate to create a contact area that at least partly overlaps the sample addition zone. Another portion extends from the contact portion to the supported periphery of the filter to define with the substrate a reservoir configured to retain the filtrate by capillary pressure between the substrate and the extending portion. The reservoir volume is based on an acute angle formed between the substrate and the extending portion of the filter and on a fluid meniscus of the filtrate. The filter and sample addition zone are configured to provide capillary pressure drawing the filtrate from the reservoir to the sample addition zone. Methods for controlling flow characteristics in a lateral-flow assay device are also described.

Abstract: An assay device for determining the concentration of multiple analytes or controls, where the device is capable of determining the presence or concentration of at least six analytes or controls includes: a fluid flow path; a liquid sample addition zone; a reagent zone downstream and in fluid communication with the sample addition zone containing one or more reagents; multiple detection zones in fluid communication with the reagent zone. The fluid flow path, which extends through the detection zones, has a length capable of having at least six detection zones linearly spaced at least a sufficient distance apart in order to discriminate each signal peak from its adjacent signal peak. The device further includes a wicking zone in fluid communication with the detection zones having a capacity to receive liquid sample flowing from the detection zone.

Abstract: An assay device includes: a liquid sample zone; a reagent zone downstream and in fluid communication with the sample addition zone containing a reagent material; a detection zone in fluid communication with the reagent zone. The detection zone has a substrate and projections which extend substantially vertically from the substrate, wherein the projections have a height, cross-section and a distance between one another that defines a capillary space between the projections capable of generating capillary flow parallel to the substrate surface. The device is capable of creating a reagent plume in the detection zone that includes liquid sample and dissolved reagent, where the width of the reagent plume extends substantially across the width of the detection zone, The device further includes a wicking zone in fluid communication with the detection zone having a capacity to receive liquid sample flowing from the detection zone.

Abstract: An assay device includes: a liquid sample zone; a reagent zone downstream and in fluid communication with the sample zone containing a reagent material; a detection zone in fluid communication with the reagent zone having capture elements bound thereto; and a wicking zone in fluid communication with the capture zone having a capacity to receive liquid sample flowing from the detection zone. The sample receiving zone, the reagent zone, the detection zone and the wicking zone define a fluid flow path and at least a part of the fluid flow path has a substrate and projections which extend substantially vertically from the substrate, wherein the projections have a height, cross-section and a distance between one another that defines a space between the projections capable of generating capillary flow parallel to the substrate surface. In addition, the fluid flow path having projections includes a corner section which changes the direction of the flow path.

Abstract: An assay device includes: a liquid sample zone; a reagent zone downstream and in fluid communication with the sample zone containing a reagent material; a detection zone in fluid communication with the reagent zone having capture elements bound thereto; and a wicking zone in fluid communication with the capture zone having a capacity to receive liquid sample flowing from the detection zone. The sample receiving zone, the reagent zone, the detection zone and the wicking zone define a fluid flow path and at least a part of the fluid flow path has a substrate and projections which extend substantially vertically from the substrate, wherein the projections have a height, cross-section and a distance between one another that defines a space between the projections capable of generating capillary flow parallel to the substrate surface. In addition, the fluid flow path having projections includes a corner section which changes the direction of the flow path.

Abstract: An assay device includes: a liquid sample zone; a reagent zone downstream and in fluid communication with the sample addition zone containing a reagent material; a detection zone in fluid communication with the reagent zone. The detection zone has a substrate and projections which extend substantially vertically from the substrate, wherein the projections have a height, cross-section and a distance between one another that defines a capillary space between the projections capable of generating capillary flow parallel to the substrate surface. The device is capable of creating a reagent plume in the detection zone that includes liquid sample and dissolved reagent, where the width of the reagent plume extends substantially across the width of the detection zone, The device further includes a wicking zone in fluid communication with the detection zone having a capacity to receive liquid sample flowing from the detection zone.

Abstract: An immunoassay reagent is provided which comprises an analyte binding agent in a diluent, and a glycosaminoglycan in an amount sufficient to reduce non-specific binding in an assay of a sample for the analyte. Provided is such an immunoassay reagent in which the analyte is troponin I, the analyte binding agent is a biotinylated anti-troponin I antibody, and the glycosaminoglycan is chondroitin sulfate. A sample composition is also provided which comprises a sample to be assayed for the presence of an analyte, an analyte binding agent, and a glycosaminoglycan other than heparin. Further provided is a method of detecting an analyte in a sample, in which non-specific binding is reduced in the method using a glycosaminoglycan.