TEST DEVICE AND METHOD

Abstract

Provided is a test device for testing an analyte in a collected sample comprising: an enclosure having at least one sample receiving port for receiving the sample; a test strip located within the enclosure, the test strip containing at least one reagent for detecting the analyte and for providing an indication showing a test result for the sample, the enclosure including a detection arrangement for allowing detection of the indication of the test strip; a sample receiving matrix positioned behind the at least one sample receiving port and having a defined saturation capacity, the sample receiving matrix being impregnated with reagents for pre-treatment of the sample and being in liquid conductive communication with the test strip. Also provided is a method for use of said test device comprising: delivering one or more samples to the at least one sample receiving port to saturate the sample receiving matrix such that a quantified amount of the sample is transferred to the test strip and an indication of the test result is effected.

Claims

1. A method for testing an analyte in a collected sample using a test device including an enclosure having at least one sample receiving port for receiving the collected sample; a test strip located within the enclosure, the test strip containing at least one reagent for detecting the analyte and for providing an indication showing a test result for the collected sample, the enclosure including a detection arrangement for allowing detection of the indication of the test strip; and a sample receiving matrix positioned behind the at least one sample receiving port and having a defined saturation capacity, the sample receiving matrix being impregnated with reagents for pre-treatment of the sample and being in liquid-conductive communication with the test strip, said method comprising: delivering one or more samples to the at least one sample receiving port to saturate the sample receiving matrix such that a quantified amount of the sample is transferred to the test strip and an indication of the test result is effected.

2-36. (canceled)

37. A test device for testing an analyte in a collected sample comprising: an enclosure having at least one sample receiving port for receiving the collected sample; a test strip located within the enclosure, the test strip containing at least one reagent for detecting the analyte and for providing an indication showing a test result for the collected sample, the enclosure including a detection arrangement for allowing detection of the indication of the test strip; a sample receiving matrix positioned behind the at least one sample receiving port and having a defined saturation capacity, the sample receiving matrix being impregnated with reagents for pre-treatment of the sample and being in liquid-conductive communication with the test strip, wherein one or more said samples can be delivered to the at least one sample receiving port to saturate the sample receiving matrix such that a quantified amount of the sample is transferred to the test strip and an indication of the test result is effected.

38. A test device according to claim 37, wherein said indication is a visual indication, said detection arrangement is a viewing arrangement and said detection is viewing.

39. A test device according to claim 37, wherein said indication is non-visual and is detected using spectrometry, fluorimetry and magnetometry.

40. A test device according to claim 37, further comprising a sample collection apparatus for collecting and delivering the one or more samples to the at least one sample receiving port.

41. A test device according to claim 40, wherein the sample collection apparatus is a brush or a brush-like apparatus having flexible or semi-flexible bristles, wherein the volume of the sample collected by the brush or brush like apparatus is less than, equal to or greater than the defined saturation capacity of the sample receiving matrix.

42. A test device according to claim 37, further comprising an obscuring arrangement for hiding at least the indication.

43. A test device according to claim 42, wherein the obscuring arrangement comprises a hinged flap locatable over the means for covering and hiding the indication, and for allowing subsequent of the indication.

44. A test device according to claim 42 [[or 43]], the obscuring arrangement comprising a hinged flap locatable over the at least one sample receiving port for covering said at least one sample receiving port.

45. A test device according to claim 44, further comprising an identifier means for sealing the flap over the at least one sample receiving port after sample collection.

46. A test device according to claim 37, wherein the detection arrangement for allowing detection of the indication comprises at least one port located in the enclosure over the test strip.

47. A test device according to claim 37, wherein the enclosure further comprises an inspection port for observing a visual indication showing the flow of the sample through the test strip.

48. A test device according to claim 37, wherein the test strip is formed from an elongate strip of hydrophilic material, one end of the test strip providing a first location for sample collection, and opposing end of the test strip providing a second location for the indication showing the test result.

49. A test device according to claim 37, wherein the sample receiving matrix is formed of hydrophilic material.

50. A test device according to claim 37, wherein the sample receiving matrix is dimensioned to provide a said defined saturation capacity for receiving one or more said samples.

51. A test device according to claim 37, wherein the sample receiving matrix is dimensioned to provide a said defined saturation capacity equal to the volume of the sample required to complete the test of the device to thereby standardise the amount of the sample used in the test.

52. A test device according to claim 37, wherein the sample receiving matrix provides filtration of solids from the collected sample before transfer to the test strip.

53. A test device according to claim 37, wherein the sample receiving matrix contains at least one reagent for solubilising and buffering the analyte in the collected sample before transfer to the test strip.

54. A test device according to claim 37, wherein the sample receiving matrix contains one or more lytic agents for lysing and releasing the contents of any cells present in the collected sample.

55. A test device according to claim 37, wherein the sample receiving matrix contains one or more surfactants to prevent non-specific binding and loss of the analyte to the matrix and the test strip.

56. A test device according to claim 37, wherein the reagent for detecting the analyte is provided in the sample receiving matrix.

57. A test device according to claim 37, wherein the enclosure is formed of a sheet material and including a front panel wherein is located at the at least one sample receiving port, and the means for allowing viewing of the visual indication of the test strip, and a rear panel for supporting the test strip, the test strip being located between said front and rear panels.

58. A test device according to claim 57, wherein the sheet material is plastic.

60. A test device according to claim 57, wherein the sheet material is waterproof cardboard.

61. A test device according to claim 60 wherein said reagent for detecting haemoglobin is anti-globin antibody conjugated to a visualisation means.

62. A test device according to claim 61 wherein said anti-globin antibody is impregnated either within the sample receiving matrix or downstream from said sample receiving matrix.

63. A test device according to claim 37 wherein said test strip additionally includes a reagent for detecting haem.

64. A test device according to claim 63 wherein said reagent for detecting haem is located at the distal end of the test strip, preferably beyond the immunodetection zone.

65. A test device according to claim 64 wherein said reagent for detecting haem is a peroxidase reagent and a chromogen.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] It will be convenient to further describe the invention with respect to the accompanying drawings, which illustrate a preferred embodiment of the test device according to the present invention. Other embodiments of the invention are possible, and consequently, the particularity of the accompanying drawings is not to be understood as superseding the generality of the preceding description of the invention.

[0047] In the drawings:

[0048] FIG. 1 is a front view of a first embodiment of a test device according to the present invention showing the sample receiving port.

[0049] FIG. 2 is a front view of the test device of FIG. 1 showing the viewing port.

[0050] FIG. 3(a) is a front view of an embodiment of a test device of the invention showing the first and second flaps and inspection port. The cellphone indicates the relative size of the device.

[0051] FIG. 3(b) is a front view of the test device with the first flap open to reveal the sample addition port and sample receiving matrix.

[0052] FIGS. 4, 5 and 13 are plan views of three embodiments of the device of the present invention prior to final assembly.

[0053] FIG. 6 shows an immunochromatographic test strip according to one embodiment of the invention, including test strip, sample application (first) zone, second reagent (viewing) zone; first (disclosing) reagent (intermediate) zone, flow confirmation line of water-soluble dye.

[0054] FIG. 7 shows the inspection window in the outer panel of one embodiment of the invention, including second flap (covers the viewing port), inspection port, flow confirmation line of water-soluble dye.

[0055] FIG. 8 is a series of front views of a second embodiment of a test device according to the present invention showing the change in visual indication as a function of the test results,

[0056] FIGS. 9(a) and 9(b) are respectively an image showing the visual indication of the test device of FIGS. 4 and 5 being read using a visual detection reader and the resultant reading obtained by the reader of the visual indication,

[0057] FIGS. 10(a) and 10(b) are respectively a graphical representation of dose-response curves of the buffer system and stool system. Human haemoglobin was diluted at indicated concentrations and applied to the sample receiving port. Cards were read using a digital reader and signal intensities of control line and test line were expressed as ratio metric units.

[0058] FIG. 11(a) and (b) are respectively graphical representations of analyte stability at 25° C., and analyte stability at 40° C. in a buffer system. Human haemoglobin was diluted at indicated concentrations and applied to the sample receiving port. Cards were read using a digital reader and signal intensities of control line and test line were expressed as ratio metric units. Cards were stored at 25 degrees Celsius for 21 days and read at indicated intervals.

[0059] FIG. 12 is a product description table comparing the current commercially available quantitative fecal immunochemical test devices versus the device described herein

DETAILED DESCRIPTION OF THE INVENTION

[0060] FIGS. 1 and 2 respectively show the assembled test device 1 according to the present invention. The test device 1 includes an enclosure 3 having a front panel 5. A sample receiving port 7 is provided on one side of the front panel 5 as shown in FIG. 1. A viewing port 9 is provided on the other side of the front panel 5 as shown in FIG. 2. A first flap 15 is provided to cover the sample receiving port 7, while a second flap 17 is provided to cover the viewing port 9.

[0061] A test strip 11 is accommodated within the housing 3, and a portion of the test strip 11 can be seen through the viewing port 9 in FIG. 2. The test strip 11 contains at least one reagent for detecting an analyte within a sample being tested by the test device 1.

[0062] A sample receiving matrix 8 is positioned behind the sample receiving port 7. The purpose of the sample receiving matrix 8 is to receive the sample and facilitate the transfer of a sample delivered to the sample receiving port 7 to the test strip 11. The sample receiving matrix 8 can contain one or more reagents to solubilise and buffer any analytes in the sample before migrating to the test strip 11. The matrix 8 may also or alternatively contain one or more surfactants and lytic agents to lyse and release the contents of any cells present in the collected sample.

[0063] FIGS. 3(a) and 3(b) depict another embodiment of the device of the invention. FIG. 3(a) shows the first flap 15 covers the sample receiving port, second flap 17 covers the viewing port and inspection port 19. FIG. 3(b) shows the sample receiving port 7, sample receiving matrix 8, first flap 15, second flap 17, inspection port 19.

[0064] The collection apparatus for collecting the sample may vary depending on the application in which the tested device 1 is being used. In the case of FOBTs and FITs, the collection apparatus may be provided by a brush or brush like apparatus (not shown) having flexible or semi flexible bristles. The advantage of using such a brush as a collection apparatus is that it allows for the collection of a sample from the vicinity of a stool located within the water of a toilet bowl, the brush further collecting some of the water within the bristles of the brush. This water can subsequently act as a solvent to facilitate the liquid-conductive communication of the collected sample with the test strip 11. The brush or brush-like apparatus can also collect sufficient water to complete the test.

[0065] The sample is delivered to the sample receiving port 7. Any faecal solids within the sample are then filtered by the sample receiving matrix 8 before the remaining part of the sample is transferred to the test strip 1 by virtue of the liquid conductive communication with the test strip 11. The collected sample then migrates along the test strip 11 to areas within the strip containing the reagents (25 & 23) for detecting the analyte within the sample. In the case of FOBTs and FITs, the analyte will be haemoglobin. The test strip 11 furthermore provides a visual indication of the test result (23) that can be viewed through the viewing port 9.

[0066] FIG. 4 shows test device 1 prior to final assembly showing in more detail the various components of the test device 1. The housing 3 includes a rear panel 6, with the test strip 11 being secured to that rear panel 6. Attached to one edge of the rear panel 6 is the front panel 5 through which are respectively located the sample receiving port 7 and the viewing port 9. An inspection port 19 (which is not shown in FIGS. 1 and 2) is also optionally provided on the front panel 5 between the sample receiving port 7 and the viewing port 9. The purpose of the inspection port 19 is to allow a visual inspection of the transfer of the sample along the test strip, for example by the inclusion of a coloured dye within the test strip showing sample transfer along the test strip 11. The two flaps 15, 17 are attached to the opposite edge of the rear panel 6 from the front panel 5. The sample receiving matrix 8 is shown in FIG. 4 to be significantly larger in dimension than the area of the sample receiving port 7. The matrix 8 is so dimensioned to provide a sufficient volume to absorb one or more collected samples, and in particular, a defined saturation capacity equal to the volume of the sample required to complete the test of the test device 1 to thereby standardise an amount of the sample used in the test.

[0067] The test device 1 is assembled by folding the front panel 5 over the rear panel 6 thereby covering the test strip 11. The sample receiving part 7 is then located over a first location 21 on the test strip 11 where the sample is initially transferred from the sample receiving matrix 8. The viewing port 9 is located over a second location 23 on the test strip 11 where the visual indication showing the test result is shown. The inspection port 19 is located at an intermediate location 25 of the test strip 11 between the first and second locations 21, 23.

[0068] FIG. 5 is another embodiment of the test device and depicts front panel 5, rear panel 6, sample receiving port 7, sample receiving matrix 8, viewing port 9, test strip 11, first flap 15 (covers the sample receiving port), second flap 17 (covers the viewing port), inspection port 19, test strip first location 21 (where sample is transferred from the receiving matrix), second zone 23 (detection zone), intermediate location 25 (test strip disclosing reagent). Assembly: glue panel 5 over 6 and the right hand panel over 5.

[0069] The method used to run the test using the test device can include the following steps: [0070] a) use a brush to collect a toilet water sample; [0071] b) delivering the sample collected by the brush to the sample receiving port 7; [0072] c) confirm the transfer of the sample along the test strip 11 by visual inspection of the flow confirmation line of dye 26 through the inspection port 19; and

[0073] d) view the visual indication provided by the test strip 11 through the viewing port 9.

[0074] The brush may be sized to collect a quantity of the toilet water sample to fully saturate the sample receiving matrix 8. Alternatively, a smaller brush may be used to deliver more than one sample to fully saturate the sample receiving matrix 8.

[0075] It is also possible that the faecal contamination may cause an undesirable level of background discolouration to the test strip 11 that may obscure a borderline positive test result. The above test method can therefore be altered by using a small brush to add a toilet water sample to the sample receiving port 19;

[0076] flushing the toilet; and

[0077] using the same brush to add a “chase” of clean water from the toilet bowl to the sample receiving port 7.

[0078] It is also envisaged that the sample could be collected from the toilet water by dipping the test device 1 directly into the toilet water thereby eliminating the need for the brush or other sample collection apparatus. The portion of the test device 1 having the sample receiving port 7 is dipped into the toilet water to thereby saturate the underlying sample receiving matrix 8 with the toilet water sample. The test results can then be obtained in the same manner by viewing the visual indication provided by the test strip 11 through the viewing port 9.

[0079] The visual indication provided by the test strip 11 may be in the form of one or more lines extending across the end of the test strip 11 viewable through the viewing port 9.

[0080] FIGS. 6, 7 and 8 show a series of images of other embodiments of the test device 1 according to the present invention. The same reference numerals are used for the same features as the first embodiment of the test device 1 for clarity reasons.

[0081] The visual indication may provide a quantitative result depending on the number of lines, and the colour density of the or each line. The visual indication for progressively increasing test values are respectively shown when looking from the left most sample to the right most sample of the image, shown in FIG. 6.

[0082] More particularly, FIG. 6 shows an immunochromatographic test strip according to one embodiment of the invention, including test strip (11), sample application (21) (first zone), second reagent (viewing) zone (23); first (disclosing) reagent (intermediate) zone (25), flow confirmation line of water-soluble dye (26).

[0083] FIG. 7 shows the inspection window in the outer panel of one embodiment of the invention, including second flap (covers the viewing port) (17), inspection port (19), flow confirmation line of water-soluble dye (26).

[0084] FIG. 9 shows the visual indication of a test device 1 being read by a reader that scans the visual indication of the test device 1 and provides a graphical output as shown in FIG. 9(b). This graphical output can then provide a quantitative test value based on the visual indication.

[0085] FIGS. 10(a) and 10(b) are respectively graphs showing a graphical representation of dose-response curves of the buffer system and stool system. Human haemoglobin was diluted at indicated concentrations and applied to the sample receiving port. Cards were read using a digital reader and signal intensities of control line and test line were expressed as ratio metric units.

[0086] FIGS. 11(a) and 11(b) show the stability of the test result after storage of the device at 25° C. and 40° C. Human haemoglobin was diluted at indicated concentrations and applied to the sample application port. Cards were read using a digital reader and signal intensities of control line and test line were expressed as ratio metric units. Cards were stored at 25 degrees Celsius for 21 days and read at indicated intervals.

[0087] FIG. 12 is a table comparing the requirements and methods used with conventional FOBT and FIT with the test requirements and methods used for the test device 1 according to the present invention.

[0088] The test device 1 according to the present invention therefore allows for the immediate testing of collected samples on site without the need to use the facilities of an off site pathology lab. This self-testing aspect of the test device also makes it suitable for use in the home or in the field where no laboratory facilities are available.

[0089] While the present invention has been described with respect to its use in FOBTs and FITs, it is to be appreciated that the present invention can be used in other applications such as the sampling and analysis of other biological fluids such as blood, urine, semen and saliva, or may be adapted to analyse the presence of contaminants in ground water, or bacteria such as E. coli in food.

[0090] Persons skilled in the art will recognise that many modifications or variations may be made to the test device described in detail herein in order to suit other testing purposes or by way of adaption for optimal function, without departing from the spirit and scope of the present invention as broadly described above.