Abstract:
The present invention is directed to improving the performance of assays using a disposable assay device which includes a porous material (20) in liquid communication with a capillary track (18). In particular, the capillary track (18) is used in conjunction with the solid support to direct test sample and assay reagents directly to a defined reaction site (22) on or in the porous material (20). Signal development at the reaction site (22) indicates the assay result. The present invention is also directed to the construction of a disposable assay device (10) which includes a capillary track (18). In particular, the capillary track is formed by printing a fluid insoluble material (25a), in the reverse image of the desired capillary track (18), on a film layer (23) and then capping the printed material. Alternatively, the capillary track (18) is formed by printing a fluid insoluble material, in the reverse image (30) of the desired capillary track (18), on a porous material (25b) which is then sandwiched between two film layers (23, 26). The present invention is also directed to a drop-forming means (50) which may incorporate one or more assay reagents to allow for improved sample processing and reagent addition, mixing and incubation.
Abstract:
The present invention is directed to improving the performance of assays using a disposable assay device which includes a porous material in liquid communication with a capillary track. In particular, the capillary track is used in conjunction with the solid support to direct test sample and assay reagents directly to a defined reaction site on or in the porous material. Signal development at the reaction site indicates the assay result. The present invention is also directed to the construction of a disposable assay device which includes a capillary track. In particular, the cappillary track is formed by printing a fluid insoluble material, in the reverse image of the desired capillary track, on a film layer and then capping the printed material. Alternatively, the capillary track is formed by printing a fluid insoluble material, in the reverse image of the desired capillary track, on a porous material which is then sandwiched between two film layers.
Abstract:
Disclosed is an improved device (10) for performing agglutination reactions having at least one chamber (10) having a reaction zone and a distal zone, in which chamber agglutination reactions can be performed. The improvement comprises utilization in the device of means for controlling the overall rate of liquid flow through the chamber (22), the means comprising a layer of liquid absorbant material (22) selectively impregnated with a substance to form an impregnated region and a non-impregnated region wherein the non-impregnated region is liquid absorbant and the impregnated region is liquid-occlusive. The non-impregnated region is in liquid communication with the distal zone of the chamber (10).
Abstract:
Disclosed is a device for performing agglutination reactions comprising: in adherent relationship, a first wettable layer (1), a second liquid-occlusive layer (2) parallel to and overlying the first layer (1), and a third layer (3) parallel to and overlying the second layer (2) and having a window for observing particles. The second layer is interposed between, and is in adherent relationship to the first and third layers. The second layer (2) has at least one general slot (25) defining a channel for directing liquid conducted by capillary action through a chamber defined by the slot in conjunction with the first (1) and third (3) layers. The chamber has a proximate zone and a distal zone. The geometry of the chamber is modified to provide flow paths having different rates of flow per unit area along the paths. This arrangement of such different paths in the chamber allows agglutination reactions in the chamber to result in the formation of a non-random pattern of aggregated particles in the distal zone of the chamber. Such a non-random pattern is more readily observable than a random pattern of aggregated particles.
Abstract:
Method and apparatus for obtaining a sample of blood from a patient for subsequent diagnostic tests, e.g., glucose monitoring. In one aspect of the invention, the method comprises the steps of: (a) forming an unobstructed opening in the area of the skin from which the sample of blood is to be extracted; and (b) extracting the sample of blood from the unobstructed opening in the skin, with the aid of a vacuum and a stretching of the skin. In another aspect of the invention, an apparatus for carrying out the method described previously is provided. The apparatus comprises: (a) a device for forming an unobstructed opening in an area of skin from which said sample is to be extracted, preferably a lancing assembly; and (b) a vacuum pump. Preferably, the apparatus also includes a housing. In a further aspect of the invention, a pneumatic lancing assembly is provided. The pneumatic lancing assembly uses differential gas pressure to thrust a lancet into skin tissue. In another aspect of this invention, an article is provided for an article capable of both collecting blood and detecting an analyte in that blood. The article, which contains an appropriate detection element for determining the amount of analyte in the blood, can be used in conjunction with a meter that measures the signal generated by the detection element of the article.
Abstract:
A method for increasing the permeability of the stratum corneum by means of a source of light, preferably a laser, more preferably a pulsed laser. By increasing the permeability of the stratum corneum, access to the interstitial fluid is achieved, thereby enabling measurement of analytes in the interstitial fluid. In one aspect, the method comprises the steps of (a) providing a source of light having a wavelength of from about 930 nm to about 1040 nm; and (b) exposing a region of the stratum corneum of the patient to said source of light for a period of time sufficient to form an opening in the stratum corneum. Preferably, exposure of the region of the stratum corneum to the source of light is ceased when an amount of interstitial fluid fills the opening in the stratum corneum, which amount is sufficient to cause the scatter intensity of the light reflected from the surface of the interstitial fluid occupying the opening in the stratum corneum to differ from the scatter intensity of the light reflected from a region of the stratum corneum that is substantially free of interstitial fluid. The invention also involves an apparatus for carrying out the foregoing method.
Abstract:
The present invention is directed to improving the performance of assays using a disposable assay device which includes a porous material (20) in liquid communication with a capillary track (18). In particular, the capillary track (18) is used in conjunction with the solid support to direct test sample and assay reagents directly to a defined reaction site (22) on or in the porous material (20). Signal development at the reaction site (22) indicates the assay result. The present invention is also directed to the construction of a disposable assay device (10) which includes a capillary track (18). In particular, the capillary track is formed by printing a fluid insoluble material (25a), in the reverse image of the desired capillary track (18), on a film layer (23) and then capping the printed material. Alternatively, the capillary track (18) is formed by printing a fluid insoluble material, in the reverse image (30) of the desired capillary track (18), on a porous material (25b) which is then sandwiched between two film layers (23, 26). The present invention is also directed to a drop-forming means (50) which may incorporate one or more assay reagents to allow for improved sample processing and reagent addition, mixing and incubation.
Abstract:
A method for increasing the permeability of the stratum corneum by means of a source of light, preferably a laser, more preferably a pulsed laser. By increasing the permeability of the stratum corneum, access to the interstitial fluid is achieved, thereby enabling measurement of analytes in the interstitial fluid. In one aspect, the method comprises the steps of (a) providing a source of light having a wavelength of from about 930 nm to about 1040 nm; and (b) exposing a region of the stratum corneum of the patient to said source of light for a period of time sufficient to form an opening in the stratum corneum. Preferably, exposure of the region of the stratum corneum to the source of light is ceased when an amount of interstitial fluid fills the opening in the stratum corneum, which amount is sufficient to cause the scatter intensity of the light reflected from the surface of the interstitial fluid occupying the opening in the stratum corneum to differ from the scatter intensity of the light reflected from a region of the stratum corneum that is substantially free of interstitial fluid. The invention also involves an apparatus for carrying out the foregoing method.
Abstract:
Dispositif amélioré (10) permettant de procéder à des réactions d'agglutination, comportant au moins une chambre (10) présentant une zone de réaction et une zone distale, les réactions d'agglutination ayant lieu dans ladite chambre. L'amélioration comprend l'utilisation dans le dispositif d'un moyen de régulation du débit global de liquide dans la chambre (22), le moyen comprenant une couche de matière absorbant le liquide (22) sélectivement imprégnée d'une substance afin de former une région imprégnée ainsi qu'une région non imprégnée, ladite région non imprégnée absorbant le liquide et ladite région imprégnée arrêtant le liquide. Ladite région non imprégnée est en communication liquide avec la zone distale de la chambre (10).