READING DEVICES AND ASSAY DEVICES FOR USE THEREWITH

• US 20030044317A1
• Filed: 11/09/1994
• Published: 03/06/2003
• Est. Priority Date: 11/12/1993
• Status: Active Grant

• Current Assignee: Inverness Medical Switzerland GmbH (Abbott Laboratories)
• Original Assignee: Inverness Medical Switzerland GmbH (Abbott Laboratories)
• Inventors: CATT, MICHAEL, PRIOR, MICHAEL E., MUNDILL, PAUL H.
• Granted Patent: US 7,141,212 B2
• Time in Patent Office: Days
• US Class Current: 422/58
• CPC Class Codes: B01L 2200/12 Specific details about manufacturing devices
• CPC Class Codes: B01L 2300/0825 Test strips
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 3/5023 with a sample being transported to, and subsequently stored in an absorbent for analysis
• CPC Class Codes: G01N 2021/8618 with an optically integrating part, e.g. hemisphere
• CPC Class Codes: G01N 2021/8654 Mechanical support; Mounting of sheet
• CPC Class Codes: G01N 21/8483 Investigating reagent band test-element handling not specific to a test method G01N33/4875; analytical elements specific to chemical analysis of biological material G01N33/52; autometer with reagent band G01N35/04
• CPC Class Codes: G01N 2201/06153 the sources being LED's
• CPC Class Codes: G01N 2201/0696 Pulsed

Abstract

A method of “reading” the result of an assay effected by concentrating a detectable material in a comparatively small zone of a carrier in the form of a strip, sheet or layer through the thickness of which electromagnetic radiation such as visible light is transmissible, wherein at least a portion of one face or the carrier is exposed to incident electromagnetic radiation which is substantially uniform across the entire portion, the portion including the small zone, and electromagnetic radiation emerging from the opposite face of the carrier is measured to determine the assay result. Preferably the radiation is diffuse light.

Claims

1. An assay result measuring device for reading the result of an assay effected by concentrating a detectable material in a small zone of a porous sheet or strip, which device comprises:

a) a source of diffuse light having a wavelength that is strongly absorbed by said detectable material;

b) sensing means to sense incident light from said source;

c) means for holding said porous sheet or strip with said small zone in a light path between said source and said sensor; and

d) electronic mean connected to said sensing means, said electronic means being programmed to derive from sensed incident light a measure of the extent to which said detectable material has become concentrated in said small zone.

2. A device according to claim 1, wherein said diffuse light is pulse , and sa d electronic means is programmed to control said sensing means such that said sensing means only senses incident light phase with said pulsed light, said light preferably having a pulse frequency of at least about 1 kHz.

27. A method according to any one of the preceding claims, wherein said electromagnetic radiation is light preferably visible light.

28. A method according to any one of the preceding claims, wherein said detectable material is a particulate direct label.

3. An assay result reader, for use in conjunction with an assay device comprising a porous liquid-permeable carrier strip or sheet through the thickness of which electromagnetic radiation is transmissible, said carrier including a detection zone in which an assay result is revealed by specific binding of a detectable material directly or indirectly to a binding agent immobilised in said detection zone, detection of said material being effected as a response to said electromagnetic radiation, said assay result reader comprising:

a) receiving means for receiving at least a portion of said assay device, said portion including said detection zone;

b) reading means associated with said receiving means, said reading means comprising;

i) at least one source of diffuse electromagnetic radiation; and

ii) one or more sensors capable of detecting the intensity of said electromagnetic radiation;

said source and said sensor(s) being positioned such that when said portion of said assay device is received within said receiving means, said detection zone is disposed in the path between said source and said sensor(s).

4. An assay result reader according to claim 3, having a diffuser in from of id one or more sensors such that electromagnetic radiation from said diffuse source must pass through said diffuser before reaching said one or more sensors, and a d detection zone of said assay device being disposed in path between said diffuse source and said diffuser.

5. An assay result reader according to claim 3 or claim 4, wherein said electromagnetic radiation is light.

6. An assay result reader according to claim 5, wherein said light is pulsed, preferably having a pulse frequency of at least about 1 kHz.

7. An assay device comprising a porous liquid-permeable carrier strip or sheet through the thickness of which electromagnetic radiation is transmissible diffusely, said carrier being within a casing, said carried including at least one detection zone in which an assay result is revealed by specific binding of a detectable material directly or indirectly to a binding agent immobilised in said detection zone, detection of said material being effected as a response to said electromagnetic radiation, and said casing having electromagnetic radiation transmitting regions enabling electromagnetic radiation from an external source to be passed through said device, said detection zone lying in the electromagnetic radiation path between said electromagnetic energy transmitting regions.

8. An assay device according to claim 7, wherein said electromagnetic radiation comprises light, preferably visible light.

9. An assay device according to claim 7 or claim 8, wherein said detectable material is a particulate direct label.

10. An assay device according to any one of claims 7 to 9, wherein said carrier strip or sheet comprises paper, nitrocellulose or the like, preferably having a thickness not exceeding 1 mm.

11. An assay device and assay result reader combination, wherein:

a) said device comprises a porous liquid-permeable carrier strip or sheet through the thickness of which electromagnetic radiation is transmissible diffusely, said carrier preferably being within a casing or cover, said carrier including at least one detection zone in which an assay result is revealed by specific binding of a detectable material directly or indirectly to a binding agent immobilised in said detection zone;

b) said casing or cover (if present) has electromagnetic energy transmitting regions enabling electromagnetic radiation from an external source to be passed through said device, said detection zone lying in the path between said transmitting regions;

c) said assay result reader includes receiving means for receiving at least a portion of said device, said portion including said at least one detection zone, to present said at least one detection zone to reading means, said reading means incorporating a source of uniform electromagnetic radiation and one or more sensors located such that upon insertion of said device into said receiving means, electromagnetic radiation can be passed through said device and the intensity of electromagnetic radiation emerging from said device can be detected by said sensor(s).

12. Combination as claimed in claim 11, wherein said receiving means incorporates interlocking means engagable with corresponding interlocking means on said device to ensure that upon receipt of said device by said reader said detection zone(s) is located and maintained in a predetermined spacial relationship relative to said reading means.

13. Combination as claimed in claim 11 or claim 12, wherein said receiving means includes actuating means triggered by said receipt of said device, said actuating means causing said reading of said detection zone(s) to be initiated.

14. Combination as claimed in any one of claim 11 to 13, wherein said device has a casing or cover which includes internal registration means which engages with corresponding registration means associated with said carrier such that said detection zone within said device casing or cover is located in a predetermined spacial relationship relative to said interlocking means on said device casing or cover.

15. Combination according to claim 14, wherein said internal registration means comprises a pin or the like, engagable with a hole or indentation in said carrier, said detection zone being at a predetermined location on said carrier relative to said hole or indentation.

16. Combination as claimed in any one of claims 11 to 15, wherein said electromagnetic radiation from said source is diffuse.

17. Combination as claimed in any one of claims 11 to 16, wherein said electromagnetic radiation is light.

18. Combination as claimed in any one of claims 11 to 17, wherein said electronic radiation from said source is pulsed.

19. Combination claimed n any one of claims 11 to 18, wherein said carrier strip or sheet comprises paper, nitrocellulose or the like preferably having a thickness not exceeding 1 mm.

20. Combination as claimed in any one of claims 11 to 19, wherein said detectable material comprises a particulate direct label.

21. Combination as claimed in claim 11, wherein said electromagnetic radiation is visible light of a wavelength that is strongly absorbed by said particulate direct label.

22. A test kit comprising an assay device and assay result reader combination according to any one of claims 11 to 21, the assay device being one of a plurality of identical such devices provided as part of the kit.

23. A method of determining the concentration of an analyte, in a sample liquid involving use of an assay device and assay result reader combination according to any one of claims 11 to 21.

24. A method of “

reading”

the result of an assay effected by concentrating a detectable material in a comparatively small zone of a carrier in the form of a strip, sheet or layer through the thickness of which electromagnetic radiation is transmissible, wherein at least a portion of one face of said carrier is exposed to incident electromagnetic radiation which is substantially uniform across the entire portion, said portion including said zone, and electromagnetic radiation emerging from the opposite face of said carrier is measured to determine said assay result.

25. A method according to claim 24, wherein said incident electromagnetic radiation is of substantially uniform intensity across said exposed portion of said carrier.

26. A method according to claim 24 or claim 25, wherein said incident electromagnetic radiation is diffuse.