Analytical test strip
First Claim
1. An analytical test strip comprisingan elongated layer of absorbent material along which liquid may pass,upper and lower layers of liquid impermeable material sandwiching the absorbent layer therebetween, said liquid impermeable material being interrupted to enable a test substance to be brought into contact with the absorbent layer at a predetermined position therealong, and said liquid impermeable material including a viewing window through which the absorbent layer is visible for detecting a color or tone change indicating a predetermined condition of a test substance introduced at said predetermined position and having passed along the absorbent layer with one or more reagent or carrier liquids to said viewing window or region,a deformable blister defined by said liquid impermeable material in a position overlying the absorbent layer and holding at least one reagent or carrier liquid, anda liquid impermeable but rupturable diaphragm separating the blister from the absorbent layer and closing the blister with each said reagent or carrier liquid therein,said blister, said viewing window and said predetermined position for introducing the test substance being spaced apart along the test strip with said viewing window being nearest one end of the test strip, the blister having at least one integral spike formed on said liquid impermeable material and defining an inner surface portion of said blister and extending to a free end adjacent the diaphragm, whereby the diaphragm is rupturable by each spike on deformation of the blister to allow the reagent or carrier liquid to leave the blister through the opening thus formed in the diaphragm and to contact the absorbent layer.
11 Assignments
0 Petitions
Accused Products
Abstract
An analytical test strip has a flexible blister (12) thermoformed in a sheet plastics member (22), and a diaphragm (34) which closes the blister to create a reservoir for holding a reagent and/or carrier liquid (32). The sheet plastics member (22) is further formed with one or two spikes (28) the or each of which is disposed within the blister and extends in a reentrant manner towards the diaphragm where it terminates at a point. For use of the dispenser the blister is pinched by finger pressure applied by the user to cause the spike or spikes to puncture the diaphragm and release the reagent and/or carried liquid which then soaks along an absorbent layer (40) until it reaches a viewing window (20). The test substance, particularly a liquid, is applied to the absorbent layer at a cavity (16), and combines with the reagent and/or carrier liquid as it moves to the viewing window. If required, the absorbent layer may include one or more discrete areas or bands (44) of an absorbed reagent substance through which the reagent and/or carrier liquid and the test substance pass. The medical (or other) condition for which the test is being made is shown as a color or tone change of the absorbent layer as seen through the viewing window.
115 Citations
20 Claims
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1. An analytical test strip comprising
an elongated layer of absorbent material along which liquid may pass, upper and lower layers of liquid impermeable material sandwiching the absorbent layer therebetween, said liquid impermeable material being interrupted to enable a test substance to be brought into contact with the absorbent layer at a predetermined position therealong, and said liquid impermeable material including a viewing window through which the absorbent layer is visible for detecting a color or tone change indicating a predetermined condition of a test substance introduced at said predetermined position and having passed along the absorbent layer with one or more reagent or carrier liquids to said viewing window or region, a deformable blister defined by said liquid impermeable material in a position overlying the absorbent layer and holding at least one reagent or carrier liquid, and a liquid impermeable but rupturable diaphragm separating the blister from the absorbent layer and closing the blister with each said reagent or carrier liquid therein, said blister, said viewing window and said predetermined position for introducing the test substance being spaced apart along the test strip with said viewing window being nearest one end of the test strip, the blister having at least one integral spike formed on said liquid impermeable material and defining an inner surface portion of said blister and extending to a free end adjacent the diaphragm, whereby the diaphragm is rupturable by each spike on deformation of the blister to allow the reagent or carrier liquid to leave the blister through the opening thus formed in the diaphragm and to contact the absorbent layer.
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15. An analytic test strip comprising:
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a viewing window; holding means for storing a reagent or carrier liquid comprising; (i) a liquid impermeable, deformable blister and (ii) a liquid impermeable, rupturable diaphragm, wherein the blister and the diaphragm together form a storage chamber for the reagent or carrier liquid; a layer of absorbent material positioned to receive the reagent or carrier liquid from the storage chamber and to carry the reagent or carrier liquid together with a test substance to said viewing window, wherein a predetermined condition of the test substance is indicated by the color or tone of said layer of absorbent material visible through said viewing window; and at least one spike formed of said liquid impermeable material and defining an inner surface portion of said blister and extending into the storage chamber toward the diaphragm, wherein the reagent or carrier liquid in the storage chamber is brought into contact with said layer of absorbent material by rupturing the diaphragm with said at least one spike. - View Dependent Claims (16, 17, 18, 19)
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20. An analytic test strip comprising:
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a viewing window; holding means for storing a reagent or carrier liquid comprising; (i) a liquid impermeable, deformable blister and (ii) a liquid impermeable, rupturable diaphragm, wherein the blister and the diaphragm together form a storage chamber for the reagent or carrier liquid; a layer of absorbent material positioned to receive the reagent or carrier liquid from the storage chamber and to carry the reagent or carrier liquid together with a test substance to said viewing window, wherein a predetermined condition of the test substance is indicated by the color or tone of said layer of absorbent material visible through said viewing window; an opening in said test strip, including the diaphragm, to permit the test substance to be contacted with said layer of absorbent material, wherein said opening is positioned on said test strip either between the blister and said viewing window or at a location separated from said viewing window by the blister; a cover over said opening, said cover being peelably adhered to said test strip; one or more discreet bands or regions of an absorbed reagent substance positioned on said test strip between said viewing window and both said opening and the blister; and at least one spike formed of said liquid impermeable material and defining an inner surface portion of said blister and extending into the storage chamber toward the diaphragm, wherein the reagent for carrier liquid in the storage chamber is brought into contact with said layer of absorbent material by rupturing the diaphragm with said at least one spike.
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Specification