Liquid specimen testing

Abstract

Urine testing apparatus, comprising a container for a urine sample and a test capsule including a plurality of reagent pads responsive to contact with a urine sample. The pads are mutually spaced and the pads are elevated.

Description

[0001] LIQUID SPECIMEN TESTING

[0002] The present invention relates generally to liquid specimen testing and particularly, although not exclusively, to apparatus, systems and methods for urine testing.

[0003] Apparatus for testing liquid specimens is well known. If the liquid specimen is in the form of urine, then a dipstick is usually used to test the urine. The testing of urine with a dipstick is carried out many times a day in medical practices clinics and hospitals around the world. The testing of the urine is essential in the diagnosis of urinary tract infections, for screening for protein and blood in the urine, and for the diagnosis of many other conditions.

[0004] The standard way in which the urine is tested with a dipstick involves a patient filling a container with urine, and then handing the container to an authorised person such for example as a nurse, a technician or a doctor. The authorised person is required to dip the dipstick into the urine in the container, wiping off excess urine on the rim of the container. The dipstick has response portions which are contacted by the liquid specimen, which become differently coloured to indicate different characteristics, present in the urine, and which are read at predetermined time periods. The response portions are read against a result chart at predetermined time intervals of up to two minutes. The entire procedure may take a minimum of three minutes to perform effectively. The procedure is unhygienic and is prone to error if the response portions are read at incorrect time intervals.

[0005] The present inventor previously devised a point-of-care urine testing system described with reference to Figures 1 to 4.

[0006] A patient provides their urine 10 in a container (tube) 15 which is fitted with a lid 17.

[0007] A healthcare professional connects a testing cap 20 to the tube 15. The cap is individually sealed in foil blister packaging to provide reagent integrity. The cap contains reagent pads 25 for testing a number of parameters e.g. leukocytes, nitrite, urobilinogen, protein, pH, blood, specific gravity, ketone, bilirubin and glucose. Note the small gaps between reagent pads, resulting in limited room for urine to escape.

[0008] The cap 20 includes an annular deck 27 and plinths (or support blocks) 29 are upstanding from the plinth. The reagent pads 25 are secured to respective support blocks 29.

[0009] With the cap 20 secured to the tube 15 this is then inverted to expose the reagent pads 25 to the urine sample 10.

[0010] The tube / sample / cap is then loaded into a digital analyser 30 which utilises reflectance photometry to take readings of the reagent pads.

[0011] Results are displayed on the analyser 30 and also on a computer (not shown) using associated software. Data can be saved into a patient’s electronic health record.

[0012] It has been found that the current design of the urine testing container is such that in its compact format urine cannot easily drain away from the reagent pads.

[0013] Excess urine can create several problems, and these include:

[0014] • Pad to pad transmission: this is where the colour of one pad can be drawn across to another pad and therefore influencing its true colour. This problem occurs when there is a “urine bridge”, whereby there is no gap between the reagent pads as the liquid joins the two reagent pads together.

[0015] • Excess urine covering reagent pads which need to not be covered for the chemistry within them to perform effectively.

[0016] To date these problems have been dealt with by a physical manipulation of the testing container prior to visual analysis. The current procedure requires the user to tap the urine testing container onto a hard surface this procedure is designed to break the surface tension and encourage the excess urine remaining in the urine testing container to travel downwards away from the reagents. This procedure has limited effect and requires a diligent user to follow a protocol. Whilst no detrimental results have been obtained utilising this procedure it is believed that an improved user experience can be achieved through the inclusion of additional innovation.

[0017] The present invention seeks to provide improvements to sample drainage.

[0018] An aspect of the present invention provides apparatus for testing a liquid specimen, which apparatus comprises a tubular container for a liquid specimen, and a generally cylindrical test capsule including a plurality of reagent pads responsive to contact with a liquid specimen, the pads are mutually spaced, with gaps sufficiently large that there is insufficient surface tension in a specimen to counteract the effects of gravity.

[0019] A further aspect provides urine testing apparatus, comprising a container for a urine sample, and a test capsule including a plurality of reagent pads responsive to contact with a urine sample, the pads are mutually spaced and the pads are elevated.

[0020] A further aspect provides apparatus for testing a liquid specimen, which apparatus comprises a tubular container for a liquid specimen, and a generally cylindrical test capsule including a plurality of reagent pads responsive to contact with a liquid specimen, in which a plurality of respective cantilevered tabs are provided on or by the capsule upon which the reagent pads are located.

[0021] Reagent pads may be supported / elevated on simple cantilever plinths / blocks. The cantilever plinths / blocks may include a radius, facet or the like. Apparatus formed in accordance with the present invention may comprise a lid for closing the container after a liquid specimen has been provided in the container.

[0022] The test capsule may be securable to the lid when the lid is on the container.

[0023] The lid may have an openable portion which when opened permits a liquid specimen in the container to enter the test capsule.

[0024] The test capsule may have opener means for opening the openable portion on the lid.

[0025] The opener means of the test capsule may be a puncturing (or cutting, tearing or rupturing, for example) formation for puncturing the openable portion of the lid.

[0026] The openable portion of the lid may be a foil or a membrane.

[0027] In some embodiments the reagent pads are inside the test capsule and are contacted by the liquid specimen when the liquid specimen enters the test capsule.

[0028] The container may, for example, be a tube of a diameter for fitting into laboratory test equipment.

[0029] The tube may be a test tube or a primary tube.

[0030] In some embodiments the reagent pads are radially distributed, for example around the periphery of the test capsule as radial spokes, with a central flow path

[0031] A further aspect provides an analyser for analysing liquid specimen testing apparatus of the type comprising a container for a liquid specimen and a test capsule with a plurality of reagent pads, the analyser comprises agitation means for promoting drainage of liquid specimen from the test capsule.

[0032] The agitation means may be configured to act on the test capsule and / or the container.

[0033] An analyser described herein may be configured for use apparatus described herein.

[0034] A further aspect provides a method of testing a liquid specimen comprising the use of an apparatus and / or an analyser as described herein.

[0035] A further aspect provides a system for testing a liquid specimen comprising an apparatus as described herein and / or an analyser as described herein and / or a method as described herein.

[0036] In aspects and embodiments of the present invention the liquid specimen may be a urine sample.

[0037] Different aspects and embodiments of the invention may be used separately or together.

[0038] Further particular and preferred aspects of the present invention are set out in the accompanying independent and dependent claims. Features of the dependent claims may be combined with the features of the independent claims as appropriate, and in combination other than those explicitly set out in the claims.

[0039] Examples of aspects and embodiments of the present invention are shown in the accompanying drawings.

[0040] In the following description, all orientational terms, such as upper, lower, front, rear, radially and axially, are used in relation to the drawings and should not be interpreted as limiting on the invention or its connection to a closure. Example embodiments are described below in sufficient detail to enable those of ordinary skill in the art to embody and implement the systems and processes herein described. It is important to understand that embodiments can be provided in many alternate forms and should not be construed as limited to the examples set forth herein.

[0041] Accordingly, while embodiments can be modified in various ways and take on various alternative forms, specific embodiments thereof are shown in the drawings and described in detail below as examples. There is no intent to limit to the particular forms disclosed. On the contrary, all modifications, equivalents, and alternatives falling within the scope of the appended claims should be included. Elements of the example embodiments are consistently denoted by the same reference numerals throughout the drawings and detailed description where appropriate.

[0042] The terminology used herein to describe embodiments is not intended to limit the scope. The articles “a,” “an,” and “the” are singular in that they have a single referent, however the use of the singular form in the present document should not preclude the presence of more than one referent. In other words, elements referred to in the singular can number one or more, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes,” and / or “including,” when used herein, specify the presence of stated features, items, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, items, steps, operations, elements, components, and / or groups thereof.

[0043] Unless otherwise defined, all terms (including technical and scientific terms) used herein are to be interpreted as is customary in the art. It will be further understood that terms in common usage should also be interpreted as is customary in the relevant art and not in an idealized or overly formal sense unless expressly so defined herein. There are two main areas for the improvements: in-container drainage; and inanalyser drainage.

[0044] In-container drainage

[0045] An embodiment is shown in Figure 5: larger diameter, therefore greater gap between the reagent pads.

[0046] The detail seen in the image is the gaps between the reagents. By placing the reagents on a larger diameter ‘pitch’ the gaps between the reagents increases. This gap is sufficiently large that there is insufficient surface tension in the urine to counteract the effects of gravity. Gravity therefore pulls the droplets downwards, eliminating the bridging effect.

[0047] A further embodiment is shown in Figure 6A & Figure 6B. Undercut design allowing urine to easily flow away.

[0048] This is the changing of design from the current plinths, whereby urine gets trapped by surface tension in between plinths due to an overhung design. The component is most likely to be a separate component due to difficulties in manufacturing.

[0049] In this embodiment, instead of plinths upstanding from the deck 227, cantilevered support tabs 235 project radially inwards and receive reagent pads 225.

[0050] As seen in the images the plinths have been entirely removed and the reagents are secured solely via a connection to the circumference therefore eliminating features underneath the reagents which can inhibit excess urine departing.

[0051] In-analyser drainage

[0052] As previously discussed, there is a procedural step required by the user between the submersing of the reagents and the insertion into the analyser for reading of the reagents colour changes. It is the intention of some embodiments to replace this user procedure with an analyser procedure.

[0053] This procedure includes the use of vibration or very small movement / manipulation. The procedure is within the device and automated, therefore taking away the task for the user, hence improving the user experience and opening the test to others with no / limited training.

[0054] The movement force inside the sample analyser will be applied to the urine testing container (any part). The movement for example if a vibrating feature will hold, grip, press up to or have the urine testing container resting upon it. The forces exerted from this external component will transfer energy into the urine testing container. The introduction of this energy will look to reduce the effectiveness of surface tension forces retaining excess urine in undesired locations. This mechanism will in effect help drain the test capsule.

[0055] Figure 7: side-mounted unit 350 making contact with a cap 320.

[0056] Figure 8: assembly on top of vibrating / other movement-inducing pad 460.

[0057] The principle of agitating to improve drainage could be useful for test apparatus formed in accordance with the present invention, but also for existing apparatus of the same general type, for example (such as the prior art apparatus described herein).

[0058] Figure 9 to 14 show a cap 520 formed according to a further embodiment.

[0059] The cap 520 comprises a T-beam / simple cantilever design.

[0060] Individual reagent pads 525 (eleven, in this embodiment) are separated and elevated (by around 7mm-8mm) on respective, simple cantilevered plinths 529 which are radially extending and mutually spaced. This prevents bridging of urine in use, by providing droplet inhibiting distances. Each plinth 529 is shaped generally like an upturned L, with a radius 560 formed at the intersection between the longer, vertical leg 562 and the shorter, horizontal leg 564 (upon which the pad 525 rests). Each plinth has a thinner panel 566 which means the side elevation is generally rectangular, but the end elevation is T-shape.

[0061] A T-shape is formed when looking from a plan view. T-shape when looking from inside out. The upright has a small support on the outer circumference, hence making the T-shape when looking as a section view.

[0062] A narrow section provides height.

[0063] The pad width is around 2mm-3mm e.g. about 2.6mm.

[0064] Space in between plinths and under the reagent pads is formed to allow urine to drain out. Forces associated with drainage are greater than those that would otherwise cause the urine to stick.

[0065] 1 . If taking a side section through the new taller plinths and then looking from above they appear a T- shape with the top parallel part of the T following the circumference. The reason for not just being a simple rib is for added strength.

[0066] 2. If looking from the central hole out the OD / circumference, there is also a T-shape with the top part of the T being the part that supports the reagent pads.

[0067] The radius is used for both strength and to reduce surface area for droplet adhesion. There are radii between the plinth on the outer circumference for strength and to reduce the chance of urine pooling here too. Radii or facet (e.g. 45 degree fillet) reduce the surface area for a liquid specimen to adhere to and also reduce / eliminate pockets e.g. when two surfaces join at 90 degrees.

[0068] The position of the T for point 1 (on the circumference) leaves an open and free area for urine to drain away from the reagent pads elevated up high. An overcap 570 is provided and, together with the cap forms a test capsule 500, The overcap encloses the pads. In this embodiment the overcap is configured to provide a headspace “above” the pads of around 5mm-6mm.

[0069] Figures 9, 10, 11 , 12 and 13 show the capsule 500 connected to a sample container / tube 515.

[0070] The diameter of the test capsule entrance aperture relative to the diameter of the sample container lumen is large (e.g. at least 20%).

[0071] Although illustrative embodiments of the invention have been disclosed in detail herein, with reference to the accompanying drawings, it is understood that the invention is not limited to the precise embodiments shown and that various changes and modifications can be effected therein by one skilled in the art without departing from the scope of the invention.

Claims

CLAIMS1. Apparatus for testing a liquid specimen, which apparatus comprises a tubular container for a liquid specimen, and a generally cylindrical test capsule including a plurality of reagent pads responsive to contact with a liquid specimen, the pads are mutually spaced, with gaps sufficiently large that there is insufficient surface tension in a specimen to counteract the effects of gravity.

2. Apparatus for testing a liquid specimen, which apparatus comprises a tubular container for a liquid specimen, and a generally cylindrical test capsule including a plurality of reagent pads responsive to contact with a liquid specimen, in which a plurality of respective cantilevered tabs are provided on or by the capsule upon which the reagent pads are located.

3. Apparatus as claimed in claim 1 or claim 2, in which reagent pads are supported on simple cantilever plinths or blocks.

4. Apparatus as claimed in claim 3, in which the cantilever plinths / blocks include a radius or a facet.

5. Apparatus as claimed in any preceding claim, comprising a lid for closing the container after a liquid specimen has been provided in the container.

6. Apparatus as claimed in claim 5, in which the test capsule is securable to the lid when the lid is on the container.

7. Apparatus as claimed in claim 5 or claim 6, in which the lid has an openable portion which when opened permits a liquid specimen in the container to enter the test capsule.

8. Apparatus as claimed in claim 7, in which the test capsule has opener means for opening the openable portion on the lid.

9. Apparatus according to claim 8, in which the opener means of the test capsule is a puncturing formation for puncturing the openable portion of the lid.

10. Apparatus according to any of claims 7 to 9, in which the openable portion of the lid is a foil or a membrane.

11. Apparatus as claimed in any preceding claim, in which the reagent pads are inside the test capsule and are contacted by the liquid specimen when the liquid specimen enters the test capsule.

12. Apparatus according to any preceding claim, in which the container is a tube of a diameter for fitting into laboratory test equipment.

13. Apparatus according to claim 12, in which the tube is a test tube or a primary tube.

14. Apparatus according to any preceding claim, in which the reagent pads are radially distributed.

15. An analyser for analysing liquid specimen testing apparatus of the type comprising a container for a liquid specimen and a test capsule with a plurality of reagent pads, the analyser comprises agitation means for promoting drainage of liquid specimen from the test capsule.

16. An analyser as claimed in claim 15, in which the agitation means is configured to act on the test capsule.

17. An analyser as claimed in claim 15, in which the agitation means is configured to act on the container.

18. An analyser as claimed in any of claims 15 to 17 and configured for use with apparatus according to and of claims 1 to 14.

19. A method of testing a liquid specimen comprising the use of an apparatus and / or an analyser as claimed in any preceding claim.

20. A system for testing a liquid specimen comprising an apparatus as claimed in any of claims 1 to 14, an analyser according to any of claims 15 to 18 or a method according to claim 19.

21. Apparatus, an analyser, a system or a method according to any preceding claim, in which the liquid specimen is a urine sample.

22. Apparatus substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

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