Assay device
AssigneeSPD Swiss Precision Diagnostics GMBH
InventorsCatherine Ungeprapakom, Stephen Carlisle, Balbir Raj
Life of this patent
Estimating the term…
Abstract
The present invention provides assay devices and methods for detecting the presence of an analyte in a sample. Devices according to the invention include a reagent zone, one or more capture zones and a detection zone. Capture zones can reduce the quantity of labelled conjugate that reaches the detection zone in the presence of a negative marker in the sample and/or in the absence of a positive marker in the sample, facilitating high sensitivity and improved specificity testing.
Claims42
An assay device for detecting the presence of an analyte in a sample, the device comprising an assay flow path, the flow path comprising:
- (a) a reagent zone comprising a mobilisable labelled conjugate comprising a detectable label directly or indirectly linked to
- (i) means for associating the labelled conjugate with the analyte and means for associating the labelled conjugate with a first negative marker which may be present in the sample, and/or
- (ii) means for associating the labelled conjugate with the analyte, wherein the labelled conjugate further comprises a positive marker or positive marker conjugate a positive marker portion of which is accessible for binding and/or wherein a mobilisable positive marker or positive marker conjugate is provided separately in the reagent zone and is configured to associate with the labelled conjugate following mobilisation such that, when the labelled conjugate is associated with the positive marker or positive marker conjugate, the positive marker portion of the conjugate is accessible for binding, and/or
- (iii) means for associating the labelled conjugate with the analyte and means for associating the labelled conjugate with a positive marker, which may be present in the sample, or a positive marker or positive marker conjugate of the device, and optionally wherein the reagent zone further comprises a mobilisable positive marker or positive marker conjugate for immobilisation downstream of the reagent zone,
- (b) one or more capture zones, wherein
- (i) if the reagent zone comprises option (i),
- at least one capture zone comprises an immobilised capture species configured to capture a complex comprising the labelled conjugate and the first negative marker wherein capture of the complex is preferably achieved by a specific binding reaction with first negative marker,
- (ii) if the reagent zone comprises option (ii),
- at least one capture zone comprises an immobilised capture species configured to capture positive marker when present in the sample or a labelled conjugate comprising or associated with the positive marker or positive marker conjugate, wherein capture of the labelled conjugate is preferably achieved by a specific binding reaction with positive marker or positive marker conjugate,
- (iii) if the reagent zone comprises option (iii),
- at least one capture zone comprises an immobilised capture species configured to capture labelled conjugate comprising means for associating the labelled conjugate with a positive marker or positive marker conjugate, wherein the immobilised capture species comprises or consists of an immobilised positive marker or positive marker conjugate, and/or if the reagent zone comprises a mobilisable positive marker or positive marker conjugate, the at least one capture zone comprises an immobilised capture species for locating the mobilisable positive marker or positive marker conjugate at the capture zone such that the positive marker portion of the conjugate is accessible for binding, wherein capture of the labelled conjugate is preferably achieved by a specific binding reaction with the means for associating the labelled conjugate with a positive marker or positive marker conjugate,
- (c) a detection zone comprising immobilised binding reagent for capturing a complex comprising the labelled conjugate and the analyte, wherein capture of the complex is preferably achieved by a specific binding reaction with the analyte,
- wherein the or each capture zone is downstream of the reagent zone, and the detection zone is downstream of the or each capture zone.
The assay device of any preceding claim, wherein the means for associating the labelled conjugate with the analyte comprises or consists of a binding reagent, such as an antibody, that binds an epitope of the analyte.
The assay device of any preceding claim, wherein the means for associating the labelled conjugate with a first negative marker comprises or consists of a binding reagent, such as an antibody, that binds an epitope of the first negative marker.
The assay device of any preceding claim, wherein the means for associating the labelled conjugate with the analyte and the means for associating the labelled conjugate with a first negative marker are (a) identical or (b) different.
The assay device of any preceding claim, wherein the means for associating the labelled conjugate with the analyte comprises or consists of a binding reagent, such as an antibody, that binds an epitope that is shared by the first negative marker and the analyte.
The assay device of any preceding claim, wherein the means for associating the labelled conjugate with a positive marker comprises or consists of a binding reagent, such as an antibody, that specifically binds the positive marker or the positive marker conjugate.
The assay device of any preceding claim, wherein the one or more capture zones comprises an immobilised capture species that specifically binds the first negative marker.
The assay device of any preceding claim, wherein the one or more capture zones comprises an immobilised capture species that specifically binds the positive marker or the positive marker conjugate.
The assay device of any preceding claim, wherein the immobilised capture species in a capture zone binds an epitope of the first negative marker that is not present on the analyte.
The assay device of any preceding claim, wherein the reagent zone comprises a mobilisable first negative marker binding reagent that is specific for the first negative marker, linked to a first binding partner and the capture zone comprises an immobilised second binding partner for the first binding partner.
The assay device of any preceding claim, wherein the reagent zone comprises a mobilisable positive marker binding reagent that is specific for the positive marker, linked to a first binding partner and the capture zone comprises an immobilised second binding partner for the first binding partner, preferably wherein the labelled conjugate comprises a positive marker or positive marker conjugate and/or wherein a mobilisable positive marker or positive marker conjugate is provided separately in the reagent zone and is configured to associate with the labelled conjugate following mobilisation such that, when the labelled conjugate is associated with the positive marker or positive marker conjugate, the positive marker or positive marker portion of the conjugate is accessible for binding.
The assay device of any preceding claim, wherein the reagent zone comprises a mobilisable positive marker or positive marker conjugate, linked to a first binding partner and the capture zone comprises an immobilised second binding partner for the first binding partner, preferably wherein the labelled conjugate comprises means for associating the labelled conjugate with a positive marker, or a positive marker conjugate.
The assay device of any preceding claim, wherein at least one capture zone comprises a first line or region of immobilised capture species, and one or more additional lines or regions of immobilised capture species located downstream of the first line or region of immobilised capture species.
The assay device of any preceding claim, wherein the device comprises a housing that obscures a user's view of the or each capture zone.
The assay device of any preceding claim, wherein the detection zone comprises an immobilised binding reagent that specifically binds the analyte.
The assay device of any preceding claim, wherein the immobilised binding reagent in the detection zone does not bind a positive marker or a negative marker.
The assay device of any preceding claim, wherein the immobilised binding reagent in the detection zone comprises or consists of an antibody.
The assay device of any preceding claim, wherein immobilised binding reagent in the detection zone binds an epitope of the analyte that is not present in the first negative marker.
The assay device of any preceding claim, wherein the reagent zone comprises a mobilisable binding reagent that specifically binds the analyte, linked to a first binding partner and the detection zone comprises an immobilised second binding partner for the first binding partner.
The assay device of any preceding claim, wherein the analyte is indicative of the presence of a first condition and optionally a second condition, and the first negative marker is indicative of the absence of the first condition.
The assay device of any preceding claim, wherein the positive marker is indicative of the presence of a first condition.
The assay device of any preceding claim, wherein the first negative marker and the analyte share a common epitope.
The assay device of any preceding claim, wherein the first negative marker and the analyte share a common structural feature, such as a subunit of the analyte.
The assay device of any preceding claim, wherein the analyte is hCG and/or wherein the first negative marker is FSH, and/or the positive marker is a progesterone metabolite, such as P3G.
The assay device of any preceding claim, wherein the mobilisable labelled conjugate comprises an anti-alpha hCG antibody.
The assay device of any preceding claim, wherein a capture zone comprises an anti-beta FSH antibody.
The assay device of any preceding claim, wherein the mobilisable labelled conjugate comprises an anti-P3G antibody and a capture zone comprises an immobilised P3G conjugate.
The assay device of any preceding claim, wherein the mobilisable labelled conjugate comprises a P3G conjugate and a capture zone comprises an immobilised anti-P3G antibody.
The assay device of any preceding claim, wherein the detection zone comprises an anti-beta hCG antibody.
The assay device of any preceding claim, wherein the mobilisable labelled conjugate comprises an anti-alpha hCG antibody conjugated to P3G and a capture zone comprises an immobilised anti-P3G antibody.
The assay device of any preceding claim, wherein the label is gold sol or latex.
The assay device of any preceding claim, adapted to reduce the quantity of labelled conjugate that reaches the detection zone in the presence of one or more additional negative markers.
The assay device of any preceding claim, adapted to reduce the quantity of labelled conjugate that reaches the detection zone in the absence of one or more additional positive markers.
The assay device of any preceding claim, wherein if the reagent zone of option (ii) and the reagent zone of option (iii) are present, the positive marker of option (ii) is different to the positive marker of option (iii).
An assay device for detecting the presence of an analyte in a sample, the device comprising an assay flow path, the flow path comprising:
- (a) a reagent zone comprising a mobilisable labelled conjugate comprising a detectable label directly or indirectly linked to a binding reagent that binds a first negative marker and a binding reagent that binds the analyte, optionally wherein the binding reagent is anti-alpha hCG antibody,
- (b) one or more capture zones, wherein at least one capture zone comprises an immobilised capture species which specifically binds the first negative marker, optionally wherein the immobilised capture species is anti-beta FSH,
- (c) a detection zone comprising immobilised binding reagent for capturing a complex comprising the labelled conjugate and the analyte, wherein capture of the complex is preferably achieved by a specific binding reaction with the analyte, optionally wherein the immobilised binding reagent is anti-beta hCG,
- wherein the or each capture zone is downstream of the reagent zone, and the detection zone is downstream of the or each capture zone.
An assay device for detecting the presence of an analyte in a sample, the device comprising an assay flow path, the flow path comprising:
- (a) reagent zone comprising a mobilisable labelled conjugate configured for association with the analyte, wherein the mobilisable labelled conjugate is also
- i. configured for association with a first negative marker and/or
- ii. configured for association with a positive marker, and/or
- iii. comprises a positive marker or positive marker conjugate or is configured for association with a positive marker or positive marker conjugate such that the positive marker or positive marker portion of the conjugate is accessible for binding,
- (b) one or more capture zones comprising immobilised capture species for capturing the labelled conjugate when the sample contains negative marker and/or immobilised capture species for capturing labelled conjugate when the sample does not contain positive marker,
- (c) a detection zone for capturing labelled conjugate when the sample contains analyte and has not been captured by a capture zone,
- wherein the one or more capture zones are downstream of the reagent zone and the detection zone is downstream of the one or more capture zones.
The assay device of any preceding claim, wherein the capture zone reduces the quantity of the labelled conjugate that reaches the detection zone and forms a detectable signal at the detection zone in the presence the analyte when the negative marker is present in the sample and/or when the positive marker is absent from the sample.
The assay device of any preceding claim, wherein detection of a signal at the detection zone is indicative of the presence of the analyte in the sample, and the presence of a first condition in a subject from which the sample is derived.
Dependencies are inferred from the claim text.