Analytical test strip apparatus

• US 4,065,263 A
• Filed: 06/14/1976
• Issued: 12/27/1977
• Est. Priority Date: 04/02/1976
• Status: Expired due to Term

• Current Assignee: Richard G. Woodbridge III
• Original Assignee: Richard G. Woodbridge III
• Inventors: Woodbridge, Richard G. III
• Primary Examiner(s): Richman, Barry S.
• Assistant Examiner(s): Marcus, Michael S.
• Application Number:
  US05/696,231
• Time in Patent Office: 561 Days
• Field of Search: 23/253 TP, 23/230 R, 23/230 G, 23/259, 23/253 R, 206/219, 116/114 AJ
• US Class Current: 422/427
• CPC Class Codes: B01L 2400/0481 squeezing of channels or chambers
• CPC Class Codes: B01L 3/505 flexible containers not provided for above
• CPC Class Codes: G01N 2035/00237 Handling microquantities of analyte, e.g. microvalves, capillary networks
• CPC Class Codes: G01N 2035/1034 Transferring microquantities of liquid
• CPC Class Codes: G01N 31/00 Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods

Abstract

Analytical test strip apparatus for chemical, physical and biological experiments on small samples of fluids or fluid-like materials, consists of a thin, flat, hollow, pliable strip the interior including a channel completely filled with a thin layer of an inert liquid, preferably of a grease like consistency, into which liquid is introduced a small amount of the fluid to be tested, to form a movable "blister". The blister is propelled through the inert liquid, which confines it at all times front and rear, by applied external pressure. A plurality of chemical, physical, biological or detection stations are typically located in said channel. A physical station might consist of a filter membrane; a chemical station of a small pocket of chemical reagent; a detecting station of a material sensitive to pH. The stations are confined by the inert liquid filling the interior channel of the strip. In addition to forming the front and rear walls of the movable blister, the inert liquid also prevents migration of reagent located in a station, excludes air and other matters and prevents escape of noxious material being analyzed. In operation, a small portion of fluid is introduced into the strip top and the top is pinched to form a bubble or blister therein. The pinch line is drawn down the strip length forcing the blister ahead of it. As the blister proceeds down the tube, it is subjected to chemical, physical, biological and detecting operations as it passes through the different stations. One side of the tube being preferably transparent, results of the operations may be visible to the eye.

Claims

1. An analytical test strip apparatus comprising:

at least one substantially flat strip having a front layer and a back layer, said front and back layers defining a channel therebetween through which a sample of liquid may pass, said strip also including a sample input port and a terminating end, at least one of said layers being relatively pliable;

a plurality of process station means linearly located in said channel; and

,

a thin layer of an inert liquid medium located in said channel, said liquid medium adhering said two layers to each other and being strong enough to prevent the forward movement of said sample in said channel solely under the influence of gravity but weak enough to allow said sample to linearly pass in a predetermined sequence through said plurality of station means in said channel under the influence of an exterior propelling means, said liquid medium so filling said channel as to constitute the medium through which the sample is propelled, the dimensions of said liquid medium being sufficiently broad so as to substantially exclude contaminating air from said station means.

4. The apparatus of claim 1 wherein at least one of said front and back layers is made substantially of a plastic-like material.

5. The apparatus of claim 1 wherein a plurality of said strips are connected in a side-by-side relationship.

6. The apparatus of claim 1 wherein a plurality of said strips are connected in a star-shaped pattern and have their sample input ports located near a common central point.

7. The apparatus of claim 1 wherein said propelling means is a doctor blade means.

8. The apparatus of claim 1 wherein said propelling means includes a key means which may be connected to one end of the strip and rolled in such a fashion as to propel the sample ahead of the roll.

9. The apparatus of claim 1 wherein said strip includes a divider means for dividing said channel into at least two separate channels, whereby said divider means serves to divide each sample into smaller samples suitable for subsequent processing.

10. The invention of claim 1 wherein one of said station means includes a filter station, said filter station comprising a flat piece of filter material located in the channel between two partially overlapping strips.

11. The apparatus of claim 1 wherein one of said station means includes a filter station, said filter station comprising a piece of expandable material blocking said channel in a zig-zag manner.

13. The apparatus of claim 1 wherein said strip includes at least one biological station in which said sample reacts with a biological reagent.

14. The apparatus of claim 1 wherein said strip is formed from one piece of flattened plastic tubing.

15. The apparatus of claim 1 wherein said strip is formed from two separate layers of plastic joined together on their edges by a heat seal.

16. The apparatus of claim 1 wherein said propelling means comprises a first pair of rollers.

17. The apparatus of claim 14 wherein said propelling means further includes a second pair of rollers, said first pair of rollers serving to propel said sample, and said second pair of rollers serving to help contain the sample between said rollers.

18. The apparatus of claim 1 wherein one of said station means is a chemical station and another of said station means is a detection station.

19. The apparatus of claim 18 further including at least one physical station.

2. An analytical test strip apparatus comprising:

a substantially flat strip having a front layer and a back layer, said front and back layers defining a channel therebetween through which a fluid may pass, said strip also including a fluid input port and a terminating end, at least one of said layers being relatively pliable;

a plurality of process stations linearly located within said channel and including at least one temperature detection station; and

,

a thin layer of an inert liquid medium located in said channel, said liquid medium adhering said front and back layers to each other and being strong enough to prevent the forward movement of said fluid in said channel solely under the influence of gravity but weak enough to allow said fluid to pass linearly through said channel under the influence of an exterior propelling means, said liquid medium so filling said channel as to constitute the medium through which the fluid is propelled.

3. An analytical test strip apparatus comprising:

at least one substantially flat strip having a front layer and a back layer, said front and back layers defining a channel therebetween through which a sample of fluid may pass, said strip also including a sample input port and a terminating end, least one of said layers being partially translucent and at least one of said layers being relatively pliable;

a plurality of process station means linearly located in said channel;

a propelling means for linearly propelling said sample through said channel; and

,

a thin layer of an inert liquid medium located in said channel, said liquid medium adhering said two layers to each other and being strong enough to prevent the forward movement of said sample in said channel solely under the influence of gravity, but weak enough to allow said sample to pass through said channel under the influence of said propelling means, said liquid medium filling said channel so as to constitute the medium through which the sample is propelled and substantially excluding contaminating air from said station means,

wherein said sample is introduced into said top sample input port and then linearly moved toward said terminating end through said liquid medium as an air-free mass by said propelling means thereby passing said sample in a predetermined sequence through said plurality of station means located in said channel.

12. The invention of claim 12 wherein said strip includes at least one detection station comprising a clear plastic window through which optical instruments can analyze the properties of said sample.