Patent Application
20160025670
The invention relates to test devices such as diagnostic test devices. In particular the invention relates to individually packaged test devices. The invention also relates to methods of manufacturing such individually packaged test devices and use of such individually packaged test devices.
Test devices such as diagnostic test devices for carrying out diagnostic tests on fluids e.g. body fluids are well known. Examples of such test devices (also known as test sensors) include glucose test devices for testing glucose concentration in body fluids such as blood, urine or saliva. The present invention is not limited to a particular kind of test device or a particular type of test.
Test devices may have various shapes and arrangements. Test devices may be provided in the form of test strips, for example substantially planar test strips having test components for conducting a diagnostic test mounted thereon. Test strips are typically relatively thin and of generally planar construction having two major surfaces and a side wall forming the periphery of the test strip lying between the two major surfaces. Test strips may be of rectangular shape having two long edges and two short edges forming the periphery of the test strip. The present invention finds particular application to test strips but is not limited to a particular shape of test strip.
The present invention is not limited to a specific kind of test strip but finds particular application in single use test strips such as blood glucose test strips.
Blood glucose measurement is used to diagnose and manage diabetes. Electrochemical determination of blood glucose typically involves placing a liquid sample (e.g. blood, urine saliva) onto a reaction zone of a test strip which contains a reagent mixture. The reagent mixture contains an enzyme capable of reacting directly or indirectly with glucose and typically also a redox mediator. The enzymatic chemical reaction is coupled to the mediator redox reaction to enable the electrochemical determination.
The reagent mixture is sensitive to moisture and must be kept dry during storage prior to use. A desiccated plastic vial containing 25 to 50 test strips is a common storage method. Opening a vial to extract a test strip exposes the remaining test strips to deleterious ambient conditions. The desiccant material brings the relative humidity down in the re-closed vial but repeated exposure to ambient conditions when removing test strips becomes a problem as the desiccant becomes additionally loaded with moisture on each occasion and its absorbent properties are consequently reduced. Also, test strips may be removed and carried separately from the vial to avoid carrying the vial around, thus exposing the test strips to ambient conditions for a harmful prolonged period. An old vial (having fully moisture loaded desiccant) may be re-used as a “lucky” vial by some patients providing minimal moisture absorption and effectively storing the test strips in ambient conditions.
Test strips may comprise test components such as measurement electrodes, a sample inlet port, a sample chamber (in which a test reaction can occur) and an air vent. In such test strips, sample fluid typically travels through the sample chamber by capillary action and the sample chamber dimensions (e.g. width and/or height) are selected appropriately to facilitate this.
Openings forming the sample inlet port and/or air vent may be formed in one or both of the major surfaces or in the side wall along the short or long edges of the typically rectangular test strip. Where a sample inlet port is formed in a side wall of a short edge, this is termed an “end fill” test strip. Where a sample inlet port is formed in a side wall of a long edge, this is termed a “side fill” test strip. Where a sample inlet port is formed on an upper major surface of a test strip, this is termed a “top fill” test strip.
One problem with test strips is degradation of reactants provided in test components due to contact with air and/or moisture and/or light (e.g. in air). This can provide inaccurate test results, and reduces shelf life and open packaging life of test strips.
Other problems include test strip handling such as packaging, extracting from packaging, picking up and manipulating the strip, locating the strip (or at least one end of) in a metering device (if required) and disposal of a used strip after the test.
Some of the problems of the vial are overcome by individually wrapping test strips in a sealed moisture proof foil laminate pouch (for example by flow wrapping).
Thus, packaging for test devices such as test strips may comprise flip top vials as described above or cartridges in which multiple test strips (typically from the same batch and having the same calibration code (if required)) are stored in a single flip top vial or cartridge. Test strips can be packaged in groups of 10, 20, 25, 50 etc. Alternatively, individual packaging for test strips has been provided by some manufacturers in which each test strip is placed between separate top and bottom covers sealed together to surround the periphery of the test strip to provide a moisture proof foil laminate pouch in a process known as flow wrapping. The top and bottom covers form in effect a sealed bag within which the test strip is freely movable.
Both the vial and pouch options present the user with issues relating to usability. Test strips stored in a vial can be difficult to remove one at a time as they are quite small and tend to come out in multiples. Foil pouches can be difficult to access due to the robust nature of the foil.
Packaging large volumes into vials or pouches requires machines to singulate test strips on a separate line which typically run at slower rates than the other test strip production processes presenting manufacturing/resource planning difficulties.
Where individual packaging about each test strip is provided, the user faces the additional challenges with opening the packaging and extracting the test strip as well as handling and locating the test strip in the metering device. It should be remembered that elderly, infirm or diabetic patients may have trouble with fine motor skills and impaired sensitivity of the hands and fingers. Furthermore, individual packaging can produce unsightly and difficult to handle packaging waste. In some instances used strips may be reinserted into packaging for disposal. This may be difficult for users to do again requiring fine motor skills and finger sensitivity.
Often used strips and packaging are disposed of separately with patients or carers having to handle contaminated used test strips.
As such there is interest in seeking to address these and other problems by identifying new packaging configurations that aim to: protect each test strip from the effects of moisture and/or improve the ease of use in accessing individual test strips, and/or reduce the cost and complexity of manufacture of such test strips.
G1245999 ELFAST describes an integrated testing strip and package for a reagent having a removable covering leaf attached to the strip to protect at least the surface of the liquid absorbing material (containing colour change reagent), the covering leaf and the test strip being made of an impervious laminate of aluminium foil and plastic, the liquid absorbing layer being sandwiched between the strip and the covering leaf. ELFAST considers strip handling and describes an end of a test strip remote from the testing end of sufficient length so that it can conveniently be held between the fingers of a user. Such an arrangement may improve utility of strip handling for users, but also increases cost of manufacture impacting negatively on the amount of materials required per strip, the size of the manufacturing line (to cope with multiple strips of increased length), the size and cost of secondary packaging such as vials/cartridges.
U.S. Pat. No. 6,558,528 MATZINGER describes electrochemical test strip cards that include integral desiccant. Electrochemical test strip precursors are provided having dry reagent in a reaction chamber bounded by opposing (top and bottom) electrodes, the reaction chamber being in gaseous communication with an integrated desiccant. Once singulated, a sample inlet port and air vent are provided in the side walls of the test strip along a long edge to form an “edge fill” test sensor. Top and bottom covers of aluminium foil and acrylic are provided. MATZINGER aims to make less use of packaging materials and provide a strip that, by utilising foil singulated strips containing desiccant, remains dry enough to last at least a month, the desiccant being less than 80% exhausted after 30 days. MATZINGER does not address strip handling.
WO2007/057704 LONG describes a disposable device comprising a first portion having a fluid application port, a handle portion hingedly attached to the first portion which normally lies in the plane of the first portion. Grip means arranged to facilitate manual handling by a user deflectably coupled to the first portion at a hinge portion are described. Insertion using the handle portion and removal of the test device from a metering device using a second portion deflectably coupled to the first portion at a hingable portion are described; the sample application zone being located between the first and second portions of the device. LONG appears to address some problems associated with strip manipulation to insert and remove test strips hygienically from a metering device. LONG does not address strip packaging and manipulation challenges associated therewith. Nor does LONG address challenges of reagent degradation.
The Alere DETERMINE HIV 1/2 Ag/Ab Combo test available from Alere Limited, Stockport, Cheshire, UK is an example of a packaged test strip.
The problems of handling a strip and any associated packaging before and/or during and/or after a test remain, as do the problems of degradation of reagents over time due to moisture ingress.
The present invention seeks to alleviate one of more of the problems described herein.
In a first aspect the invention provides a test device comprising: a test strip having first and second major surfaces and comprising: a proximal portion for bearing contacts for a metering device, an intermediate portion for receiving a sample comprising a test area on the first major surface, the test area comprising at least one test component; a separable distal portion; and in which the test device further comprises: a cover leaf extending over at least part of one of the major surfaces of the test strip so as to seal the test area and having a non-removable portion attached to the separable distal portion of the test strip.
Optionally, the removable cover leaf extends over the first major surface of the test strip to seal the test area in respect of the first major surface.
Optionally, the cover leaf comprises a removable cover leaf having a removable portion extending over at least part of one of the major surfaces of the test strip so as to seal the test area.
Optionally, the removable cover leaf extends over the second major surface of the test strip so as to seal the test area in respect of the second major surface.
Optionally, a removable cover leaf extends over the first major surface of the test strip to seal the test area in respect of the first major surface and a further removable cover leaf extends over the second major surface of the test strip so as to seal the test area in respect of the second major surface. Thus one or two removable cover leaves according to the invention may be provided, each associated with one of the first and second major surfaces of the test strip.
Optionally, the separable distal portion of the test strip is separable so as to be movable with respect to at least the intermediate portion of the test strip.
Optionally, the separable distal portion of the test strip is rotatable with respect to the intermediate portion and/or to the proximal portion of the test strip.
Optionally, the separable distal portion of the test strip is connected to the intermediate portion and/or proximal portion of the test strip by one or more hinge portions.
Optionally, the separable distal portion comprises at least one arm lying alongside the intermediate portion of the test strip.
Optionally, the separable distal portion forms a frame about the intermediate distal portion of the test strip.
Optionally, the separable distal portion is U-shaped having two laterally spaced arms lying alongside the intermediate portion and a distal cross strut therebetween to form a frame about the intermediate portion.
Optionally, a hinge portion is provided between the or each arm and the proximal portion.
Optionally, the separable distal portion of the test strip lies immediately adjacent the intermediate portion of the test strip.
Optionally, the size and/or shape of the periphery of the separable distal portion opposite the intermediate portion corresponds with the size and/or shape of the opposing periphery of the intermediate portion whereby these lie immediately adjacent one another.
Optionally, the intermediate portion is of narrower width than the proximal portion and forms an intermediate tip portion comprising a tip.
Optionally, the separable distal portion of the test strip forms a frame about the intermediate portion of the test strip, and the removable portion of the removable cover leaf extends over at least the intermediate portion and the non-removable portion of the removable cover leaf extends over the frame.
Optionally, the removable cover leaf extends over the second major surface of the test strip forming a first removable cover leaf on the second major surface of the test strip and a second cover leaf is provided extending over the first major surface of the test strip.
Optionally, the second cover leaf over the first major surface is completely detachable from the test strip.
Optionally, the second cover leaf comprises a removable portion extending over at least part of the first major surface of the test strip so as to seal the test area and having a non-removable portion attached to the proximal portion of the test strip.
Optionally, the second cover leaf comprises a second removable cover leaf having a removable portion extending over at least part of the first major surface of the test strip so as to seal the test area and having a non-removable portion also attached to the separable distal portion of the test strip.
Optionally, the separable distal portion is separable so as to be completely detachable from the remainder of the test strip.
Optionally, the separable distal portion is frangibly connected to the intermediate portion and/or proximal portion whereby the separable distal portion and associated removable portion of the removable cover leaf are detachable from the remainder of the test strip.
Optionally, the separable distal portion is separable by bending along a lateral axis across the test strip with respect to the remainder of the test strip and/or twisting along a longitudinal axis along the test strip with respect to the remainder of the test strip.
Optionally, the test component comprises a sample chamber extending from the intermediate portion into the separable distal portion and detachment of the separable distal portion opens and/or forms a sample inlet port.
Optionally, the test device comprises a removable portion of the removable cover leaf extending over at least part or all of the intermediate portion.
Optionally, the test device comprises a removable portion of the removable cover leaf extending over at least part or all of the proximal portion.
Optionally, the removable portion comprises a free tab for gripping.
Optionally, the removable portion of at least one removable cover leaf comprises pre-selected regions attached to the test strip surrounding at least part or all of the intermediate portion, or at least the test area, of the test strip. Optionally, the pre-selected regions of the removable portion attached to the test strip are attached in a manner so that at least part or all of the removable portion of the removable cover leaf is not attached, or is not attached to any appreciable extent, to the intermediate portion, or at least the test area, of the test strip. Optionally said pre-selected regions of attachment comprise a weld and/or seal and/or adhesive layer or other joint mechanism. Optionally, said pre-selected regions of attachment have different attachment strengths in the non-removable portion compared to the removable portion, the non-removable portion being fixedly attached to the test strip and the removable portion being removably attached.
Optionally, the non-removable portion of the removable cover leaf attached to the separable distal portion of the test strip comprises a distal portion of the first removable cover leaf.
Optionally, first and/or second removable cover leaves are permanently attached to respective major surfaces of the separable distal portion. Optionally, the non-removable portion of the first removable cover leaf is permanently attached to the separable distal portion of the test strip and the removable portion is peelably attached to at least the intermediate portion of the test strip.
Optionally, the non-removable portion of at least one removable cover leaf is attached to the separable distal portion of the test strip and the attachment mechanism comprises a weld and/or seal and/or adhesive or other joint mechanism. Optionally, the attachment mechanism is permanent.
Optionally, the test strip comprises a substrate having a proximal portion, an intermediate portion and a separable distal portion. Optionally, the substrate is an integral component.
Optionally, the substrate comprises one or more lines of weakness and/or cuts delineating between the intermediate portion and the separable distal portion. Optionally, the substrate comprises one or more lines of weakness delineating between the proximal portion and the separable distal portion. Optionally, the first removable cover leaf (and/or second removable cover leaf where provided) comprises one or more lines of weakness and/or cuts delineating between the removable portion of the removable cover leaf and the remaining non-removable portion.
Optionally, the separable distal portion is rectangular or substantially rectangular. Optionally the test strip is rectangular or substantially rectangular.
Optionally, a pre-selected continuous region of attachment is provided on the removable portion of at least one removable cover leaf having an inner region of non-attachment sized and shaped to correspond to the intermediate portion.
Optionally, the removable portion of at least one removable cover leaf is rectangular or substantially rectangular. Optionally, the non-removable portion is rectangular or substantially rectangular.
Optionally, at least one removable cover leaf comprises a moisture barrier layer e.g. metal foil.
Optionally, at least one removable cover leaf comprises a desiccant loaded plastic layer.
Optionally, at least one removable cover leaf comprises a thermoplastic layer inwardly facing towards the test strip or desiccant loaded thermoplastic layer inwardly facing towards the test strip. Optionally, at least one removable cover leaf is a laminate comprising a plastic outer layer, a central moisture barrier layer and an inwardly facing tie-in layer.
Optionally, contacts are provided and these are not covered by a cover leaf or a removable cover leaf according to the invention.
Optionally, the test device comprises a removable cover leaf having a removable portion extending over at least part of one of the major surfaces of the test strip so as to seal the test area and a non-removable cover leaf on the other major surface of the test strip having a first non-removable portion extending over and attached to at least a part of said major surface of the test strip so as to seal the test area and having a second non-removable portion attached to the separable distal portion of the test strip.
In a second aspect, the invention provides a test device in which the cover leaf comprises a non-removable cover leaf having a first non-removable portion extending over and optionally attached to at least part of the major surface of the test strip so as to seal the test area and having a second non-removable portion attached to the separable distal portion of the test strip.
Optionally, the test device comprises two of said non-removable cover leaves, one on each major surface of the test strip.
Optionally, at least one cover leaf is frangible to facilitate separation of the first and second non-removable portions upon removal of the separable distal portion.
Optionally, at least one cover leaf is piercable by the intermediate portion upon removal of the separable distal portion e.g. by rotation.
In a third aspect the invention provides a test device comprising: a test strip having first and second major surfaces and a test area comprising at least one test component; a first cover leaf comprising a moisture and/or desiccant barrier layer on a first major surface; a second cover leaf comprising a moisture and/or desiccant barrier layer on a second major surface; wherein at least one of the cover leaves is at least partly removable from the test strip to expose the test area.
Optionally, one or more removable cover leaf comprises a moisture barrier layer e.g. metal foil.
Optionally, one or more removable cover leaf comprises a desiccant loaded plastic layer.
Optionally, one or more removable cover leaf comprises a thermoplastic layer inwardly facing towards the test strip or a desiccant loaded thermoplastic layer facing inwardly towards the test strip. Optionally, one or more removable cover leaf is a laminate comprising a plastic layer, a central moisture barrier layer and an inwardly facing tie-in layer.
Optionally, one or both cover leaves are removable, optionally, one or both are completely removable.
Optionally, the test strip comprises a separable distal portion which is removable along with one or both cover leaves.
Optionally, the separable distal portion is hingedly connected to the remainder of the test strip.
Optionally, the separable distal portion is detachable from the remainder of the test strip.
Optionally, the contacts are not covered by a removable cover leaf.
In a fourth aspect the invention provides a method of manufacturing a test device as described herein comprising: forming a test strip having first and second major surfaces and comprising: a proximal portion for bearing contacts; an intermediate portion for receiving a sample comprising a test area comprising at least one test component; a separable distal portion; applying a first removable cover leaf extending over at least part of one of the major surfaces of the test strip so as to seal the test area.
Optionally, the method comprises: attaching removably pre-selected regions of a removable portion of the removable cover leaf to the major surface of the test strip to form a seal about the test area; attaching non-removably a non-removable portion of the first removable cover leaf to the separable distal portion of the test strip.
Optionally, the method comprises: permanently attaching at least part of the non-removable portion of the removable cover leaf to the separable distal portion of the test strip.
Optionally, the method comprises: applying a cover leaf or a second removable cover leaf over the other major surface.
Optionally, the method comprises: attaching removably pre-selected regions of a removable portion of the second removable cover leaf to the major surface of the test strip to form a seal about the test area; attaching non-removably a non-removable portion of the second removable cover leaf to the separable distal portion of the test strip.
Optionally, the method comprises permanently attaching at least part of the non-removable portion of the second removable cover leaf to the separable distal portion of the test strip.
Optionally, the method comprises providing cuts and/or lines of weakness in the test strip and/or in one or each cover leaf before and/or during and/or after assembly of the test device.
Optionally, the method comprises providing any of the features of the device as described herein.
In a fifth aspect the invention provides a method of use a test device as described herein comprising: a) optionally removing a portion (optionally a removable portion) of a cover leaf (optionally a removable cover leaf) to expose the test area; b) removing a separable distal portion of the test strip; c) inserting the proximal portion of the test strip into metering device; d) applying a sample to the sample inlet port, and e) obtaining a measurement reading from the metering device.
Optionally, in the method step (a) and/or (b) occurs before step (c). Optionally in the method step (a) occurs before step (b). Optionally in the method step (c) occurs before step (a) and (b).
Optionally, in the method steps (a) and (b) occur substantially simultaneously.
In a sixth aspect the invention provides a test device card comprising two or more test devices as described herein having frangible connections between test devices.
Optionally, the test card comprises a row of test devices and/or comprising 2, 3, 4, 5, or 6 test devices as described herein.
Typically, in use, removal of the removable portion of the removable cover leaf from the intermediate portion exposes the test area (preferably in one example embodiment unsealing the sample inlet port and/or air vent) and separation (e.g. by movement or detachment) of the separable distal portion of the test strip facilitates access to the sample inlet port (particularly in an “end fill” test strip). Preferably, the sample inlet port is located adjacent to the separable distal portion. Optionally, the sample inlet port is located on a major surface of the test strip (e.g. on a first or upper major surface providing a “top fill” test strip). Preferably, the sample inlet port is located in a side wall along an edge of the test strip (e.g. a short edge for an “end fill” or a long edge for a “side fill” test strip).
Preferably the separable distal portion is removable by rotational displacement (e.g. bending or twisting) with respect to the proximal and intermediate portions and/or by detachment from the intermediate portion. Preferably, the separable distal portion is removed by bending about one or more hinge portions, typically out of the plane of a major surface of the test strip (for example about an axis between the short edges of the test strip or about an axis extending between the long edges of the test strip).
The following drawings illustrate embodiments of the invention by way of example only. In the following figures, like reference numerals refer to like features.
Any feature of any embodiment of any aspect of the invention described herein may be combined with any other feature in any other embodiment of any aspect of the invention described herein. Further embodiments will be envisaged by those skilled in the art from the information disclosed herein and all alternative embodiments are considered to be embodiments of the invention, the invention to be limited by the appended claims.
In the previous and following descriptions and appended claims, the term ‘test device’ is used to refer to a combination including, but not limited to, a test strip in combination with individual packaging for the test strip in the form of one or more associated cover leaf or leaves, and the term ‘test strip’ is used to refer to a test sensor for conducting a test (e.g. a diagnostic test) of any suitable size or shape, although preferably of generally or substantially planar construction having upper and lower major surfaces and a side wall (preferably a relatively thin side wall) between said upper and lower major surfaces.
The present invention is not limited to a particular kind of test device or a particular type of test.
The present invention finds particular application to test strips of generally or substantially planar construction having upper and lower major surfaces. The invention is not limited to a particular shape of test strip.
In the previous and following descriptions and appended claims, where the terms ‘upper’ and ‘lower’ are used with respect to the major surfaces of a test strip, test device or any portion of a test strip or test device, typically the ‘upper’ major surface refers to the major surface on which, in which, or in association with which, at least one test component for conducting a test (such as measurement electrodes, reagent, conductive tracks, sample chamber and hydrophilic layer) is formed and the ‘lower’ major surface of a test strip, test device or any portion of a test strip or test device refers to the major surface opposing the ‘upper’ major surface. These terms are not intended to be limiting unless the context dictates otherwise.
Similarly the terms ‘first’ and ‘second’ when used in connection with removable cover leaves and for major surfaces is not intended to be limiting unless the context dictates.
In the previous and following descriptions and appended claims, the terms ‘proximal’, ‘intermediate’ and ‘distal’ may be used with respect to a test device or test strip or any component of a test device or test strip e.g. a test strip, a hydrophilic layer, a spacer layer, base substrate, upper removable cover leaf or lower removable cover leaf, to indicate corresponding proximal, intermediate and distal portions of each test device, test strip or component.
Nevertheless, unless indicated otherwise by the context, the terms ‘proximal portion’, ‘intermediate (tip) portion’ and ‘separable distal portion’ are intended to refer to the test strip component of the test device.
Test components, such as measurement electrodes, sample inlet port, sample chamber and air vent, may be provided on a major surface of a base substrate so as to provide a test area described herein as being ‘on’ the corresponding major surface of a test strip. It will be understood by those skilled in the art from the disclosure herein that the one or more test components if described as being ‘on’ a major surface of the test strip may be located upon or associated with or form part of that major surface of the test strip, for example as described herein. This is somewhat similar to patterns printed on cloth, in that the patterns are printed upon a surface of cloth but in effect form part of that surface of the cloth and are described as being ‘on’ the cloth but in effect form part of that surface of the cloth.
These test strip components are omitted to aid clarity. Thus, test strip 20 comprises an upper first major surface 28 bearing at least one and typically multiple test strip components (not shown) and an opposing lower second major surface 29.
Contacts 18, providing external electrical connection to the test strip components, are provided on an upper major surface 28 of test strip 20. In this example, contacts 18 terminate at a proximal portion of test strip 20 but alternative arrangements can be envisaged. Here, test device 10, test strip 20 and cover leaves 22 and 24 are generally rectangular, but again alternative (including but not limited to square, round, elliptical, oval) shapes can be envisaged.
Test strip 20 has a proximal portion 12, an intermediate tip portion 14 and a separable distal portion 16. Proximal portion 12 bears contacts 18. Intermediate tip portion 14 is narrower than proximal portion 12 and forms a narrower tongue extending from proximal portion 12 towards the opposing distal end of the test device. Intermediate tip portion 14 is surrounded on three sides by separable distal portion 16 when viewed from above (or below). Thus, in this example embodiment, intermediate tip portion 14 is narrower than proximal portion 12 and also narrower than separable distal portion 16. Further, in this (and other) embodiments, separable distal portion 16 is U-shaped when viewed from above having two spaced apart lateral arms, each connected directly to proximal portion 12 and a distal cross-strut connected therebetween.
Separable distal portion 16 forms a U-shaped bendable frame about intermediate tip portion 14, the U-shaped bendable frame being hingedly connected to proximal portion 12.
The inner facing periphery of separable distal portion 16 matches the outer periphery of intermediate tip portion 14, preferably being of substantially the same size and/or shape. Thus, the separable distal portion surrounds and protects the side walls forming the periphery of the intermediate tip portion 14. A number of cuts 36 through test strip 20 and optionally cover leaf layers 22, 24 may be used to create and define the periphery of intermediate tip portion 14. It is preferred that the inner facing periphery of separable distal portion 16 lies immediately adjacent the periphery of the intermediate tip portion 14 about its three protruding sides. In a strip of the order of few cm long and around 0.5 cm wide, a small gap of the order of a few hundred microns to a few millimetres (up to 5 mm) may be used. The gap may be 5 mm or less, although a gap of 1 or 2 mm or less is preferred. Preferably, the gap between intermediate tip portion 14 and separable distal portion 16 is the same, within manufacturing tolerances, around substantially all the periphery of the intermediate tip portion 14.
It is noted that at the distal end of intermediate tip portion 14, the corners are bevelled to create a slightly narrower distal tip end on a tip formed by intermediate tip portion 14. This may serve to guide a user as to where to place a sample.
In the example embodiment shown in
In this and other embodiments typically the first (and/or where provided, second) removable cover leaf according to the invention will be formed of a single piece (e.g. a single piece of optionally laminated material) with, preferably, predefined removable and non-removable portions. Alternatively, the first and/or second removable cover leaves may be formed from two or more separate pieces (e.g. separate pieces of (optionally laminated) material) forming removable and non-removable portions which pieces may be joined together to form a complete removable cover leaf.
In this and other embodiments, the terms ‘removable portion’ and ‘non-removable portion’ when used in connection with a removable cover leaf according to the invention indicate the following: the portion may be moved away from its initial position (for example, overlaying a major surface of a test strip 20 and/or in line with a plane through a major surface of the test strip)—a ‘removable portion’. Alternatively, the portion may not be moved from its initial position (for example, overlaying a major surface of a test strip 20 and/or in line with a plane through a major surface of the test strip)—a ‘non-removable portion’.
In
The ‘removable portion’ e.g. removable portion 32, of a removable cover leaf may be peelably adhered or sealed to a major surface of a test strip. One or both of the ‘non-removable portions’ e.g. non removable portion 34A and further non-removable portion 34B may be non-peelably (e.g. permanently) attached by adhering or welding to the test strip. Alternatively the non-removable portions (34A, 34B) may be provided with peelable or non-permanent adhesive to provide adhesion to the major surface of the test strip, but is arranged so as not to be removable (for example by not providing a free tab for gripping). Examples of adhesives, welds, seals or joints include hot welding (e.g. thermoplastic welding using polyethylene), pressure sensitive adhesives (e.g. ethylene vinyl acetate, ethyl acrylic acid), and thermosetting adhesives (e.g. acrylic, polyurethane, natural rubber).
As will be seen hereinafter in various embodiments of the invention, or envisaged from the disclosure herein, the removable portion of a first removable cover leaf (and/or the removable portion of a second removable cover leaf where provided) may also be removable by complete detachment from the remainder of the test device (preferably along with the separable distal portion of the test strip, (e.g. see
Similarly, the separable distal portion of the test strip to which the removable portion(s) of the first (and/or second) removable cover leaf is attached, optionally permanently, may be separable by complete detachment from the remainder of the test device or may be separable by moving the separable distal portion away from its initial position with respect to part or all of the remainder of the test strip 20.
In the example embodiment shown in
Referring now to
Test strip 20 comprises a substrate with printed layers as will be described later. The substrate is typically formed as an integral component of a suitable material such as plastic. Examples of plastics used include polyethylene teraphthalate, polypropylene. Test strip 20 is provided with two laterally spaced hinge portions 30, optionally formed from a line of weakness or other hinge mechanism, joining proximal portion 12 and separable distal portion 16, and enabling separable distal portion 16 to form a bendable U-shaped frame (bendable about hinge portions 30) surrounding intermediate tip portion 14 having two arms lying alongside intermediate tip portion 14 and a cross-strut therebetween. Separable distal portion 16 has a non-removable portion 34A of first removable cover leaf 22 attached thereto. In this example embodiment both the intermediate tip portion 14 and the separable distal portion 16 are directly connected to the proximal portion 12. Preferably, there is no hinge portion between proximal portion 12 and intermediate tip portion 14.
Lower removable cover leaf 22 forming in this example embodiment a first removable cover leaf according to the invention, overlies at least part of lower major surface 29 of test strip 20. The lower removable cover leaf 22 is sealed in selected regions to lower major surface 29. In particular, preferably, the lower removable cover leaf is sealed so as to surround the periphery of the intermediate tip portion 14 (e.g. so as to seal the test area) as will be described in more detail later, but the seal does not extend over the intermediate tip portion 14 to any appreciable extent so this is not sealed to the removable portion 32 of the removable cover leaf 22 or is not sealed to any appreciable extent. The seal may be permanent or temporary (e.g. a thermo plastic weld or peelable adhesive). As described above the seal may extend inwardly a little over the gap formed by cuts 36 to surround and cover the periphery of the intermediate tip portion 14. This may provide additional sealing of the side walls of intermediate tip portion 14 as the adhesive of thermoplastic may creep into the gap. Examples of seal layouts (e.g. thermo weld or adhesive layouts) for use with cover leaves will be described in more detail below. Thus, typically the lower removable cover leaf 22 is not sealed to the intermediate tip portion 14, so that, the removable portion 32 of the lower removable cover leaf 22 can be removed without pulling on or bending the intermediate tip portion 14 when separable distal portion 16 and associated non-removable portion 34A of removable cover leaf 22 are rotated about hinge portions 30. As described above, non-removable portion 34A of removable cover leaf 22 may be sealed, e.g. permanently welded, permanently adhered, or peelably adhered to separable distal portion 16 and moves with it. A further non-removable portion 34B may be similarly sealed to the proximal portion 12 of the test strip.
Referring to
In step 2, tab 26 is gripped and pulled by user in the direction of arrow A to peelably detach detachable cover leaf 24 from test strip 20, thereby exposing (in respect of the upper major surface) a test area of test strip 20 which test area comprises at least one test component (such as sample inlet port, sample chamber and air vent) located on intermediate tip portion 14. Strictly speaking, the test components are located, typically in layers, on the upper major surface of a base substrate to form the test strip.
In step 3, separable distal portion 16 is gripped (typically by the cross strut at a distal end thereof) and rotated about hinge portion 30 relative to proximal portion 12 and relative to intermediate tip portion 14 in the direction of arrow B. As intermediate tip portion 14 is not attached to the removable cover leaf 22, the removable portion 32 of the removable cover leaf 22 initially overlying intermediate tip portion 14 simply rotates with the separable distal portion 16 (and with non-removable portion 34A) out of the plane of the remainder of the test device (proximal portion 12 and intermediate tip portion 14) thereby exposing the lower major surface of intermediate tip portion 14. Intermediate tip portion 14 therefore stands proud of the separable distal portion 16 and removable portion 32 of removable cover leaf 22 and provides easy access for a user to a sample inlet port e.g. at an end (for “end fill”) or at a side (for “side fill”) of intermediate tip portion 14.
Separable distal portion 16 may be bendable backwards through almost 180° about hinge portion 30 to lie alongside the proximal portion 12 of the test device to provide additional length (in effect an extended ‘handle’) to the test device 10 to facilitate device handling. Thus separable distal portion 16 may be used as a handle before, and/or during, and/or after sample application and sample measurement. Furthermore as separable distal portion 16 carries removable portion 32 of removable of removable cover leaf 22, replacement of separable distal portion 16 to its initial position, in the plane containing the remainder of test strip 20, re-covers the exposed intermediate tip portion 14 about its lower major surface and about its periphery.
Referring to
In this embodiment, test device 100 comprises a test strip 20, a first (here upper) removable cover leaf 21 and a second (here lower) removable cover leaf 22. The test strip 20 is formed from an integral substrate and has three sections a proximal portion 12 (typically bearing electrical contacts 18), an intermediate tip portion 14 and a separable distal portion 16. Proximal portion 12 is optionally not completely covered by a cover leaf or is covered but not sealed to a cover leaf so electrical contacts 18 are exposed. Thus, in this and other embodiments an unused strip can be inserted (typically electrical contacts first) into a metering device before exposing test components to atmosphere. The metering device may then be usable as a handle to hold the test device 100 whilst the removable cover leaves 21 and 22 are removed by a user. Furthermore in this and other embodiments this arrangement enables the metering device to be used to conduct measurement before the removable cover leaf/leaves are removed. This pre-test measurement may be used to assess the viability of the test strip 20 and/or the degradation of the reagent and/or assess the test strip for manufacturing flaws before the test strip is used. If an error or out of scope reading is taken in a pre-test measurement, an error message can be delivered to a user before a test is conducted, reducing the possibility of an incorrect test measurement being delivered to a user and the risk of inappropriate treatment and avoiding the inconvenience of multiple wasted strips, or multiple finger sticks to obtain a sample as well as time taken conducting a wasted test.
In the example embodiment shown in
The lower major surface 29 of the test strip 20 is overlaid by a second removable cover leaf 22 having a removable portion 32 and a non-removable portion 34A overlaying the separable distal portion 16 of the test strip and a further non-removable portion 34B overlaying the proximal portion of the test strip. Lower removable portion 32, non-removable portion 34A and separable distal portion 16 are rotatable, in use, about two laterally spaced hinge portions 30 in test strip 20. Typically hinge portions 30 are formed by a line of weakness (such a score or partial cut or other hinge mechanism) in the substrate of test strip 20 across the join between the lateral arms of separable distal portion 16 and proximal portion 12. Alternatively, or preferably in addition, a hinge portion (not shown) such as a score, partial cut out or other hinge mechanism may be provided in lower removable cover leaf 22 in the region of hinge portions 30.
Upper removable cover leaf 21 may overlay at least around ¾ of the upper major surface 28 of test strip 20, having a non-removable portion 34′ attached (preferably permanently) to a distal end of separable distal portion 16 by a (preferably permanent) seam 38. Seam 38 may form part of seal 48 (see
Alternative embodiments can be envisaged in which a region of weak adhesive, or other weak seal, may be provided on intermediate tip portion 14, but this is less preferred. Similarly a profiled adhesive layer may be provided for lower removable cover leaf 22 having regions that are selectively adhered to lower major surface 29 (for example to separable distal portion 16, and the proximal portion 12) and not adhered to any appreciable extent (physically or chemically) to intermediate tip portion 14. The profiled adhesive layer may extend over the gap in the region of cuts 36 (as described above).
In the example embodiment shown in
The removable portion 32′ of the upper removable cover leaf 21 (overlaying the intermediate tip portion 14 and the arms of the U-shaped frame forming the separable distal portion 16) rotates about the axis through hinge portions 30′ in the direction of arrow C (away from the proximal portion 12), whereas the removable portion 32 of the lower removable cover leaf 22 (and the non-removable portion 34A overlaying the intermediate tip portion 14) rotates through hinge portion 30 in the direction of arrow D (towards the proximal portion 12). This arrangement of spaced, but substantially parallel axes of rotation, one for each removable portion of the upper and lower removable cover leaves 21, 22, facilitates the provision of a doubly extended handle 40 comprising separable distal portion 16 and removable portion 32 (and non-removable portion 34A) of lower removable cover leaf 22 and removable portion 32′ of upper removable cover leaf 21. This extended handle 40 greatly extends the usability of the test strip without requiring additional materials.
In step 1 of
In step 3, once removable portion 32′ is free from upper surface 28, separable distal portion 16 can be rotated about hinge portion 30 in the direction of arrow D toward proximal portion 12. Removable portion 32′, which is securely attached to separable distal portion 16 by seam 38 fixing non-removable portion 34′ to upper surface 28, can be used as a handle to facilitate rotation of separable distal portion 16. Rotation of separable distal portion 16 about lower hinge portion 30 causes separable distal portion 16 (and associated removable portion 32 and non-removable portion 34A) to rotate (and if necessary detach from) the lower major surface of intermediate tip portion 14, exposing said lower major surface and the side walls of the periphery of intermediate tip portion 14.
In step 4, separable distal portion 16 and associated removable portion 32 and non-removable portion 34A of lower removable cover leaf 22 are preferably rotated, for example, up to almost 180° about hinge portions 30 so that separable distal portion 16, removable portions 32 and 32′ and non-removable portion 34A provide an extended handle 40 for handling test device 100. Handle 40 can be used to assist insertion and/or removal of a test device 100 from a metering device. Following a test, the test strip 20, now contaminated with sample can be covered up by removable cover leaves 21 and 22, by rotating the separable distal portion 16 back to its initial position and the removable portions 32 and 32′ about their hinge portions 30, 30′ to re-cover intermediate tip portion 14.
Referring briefly to
In
As in other embodiments, removable portion 32 may be hingedly and/or frangibly connected to non-removable portion 34B (e.g. by a line of weakness) and also provides a seal about intermediate tip portion 14 on the lower surface 29 of test strip 20 without being sealed to it.
Thus, first removable cover leaf 22 has a removable portion 32 and a first non-removable portion 34A attached to separable distal portion 16 and a further non-removable portion 34B both selectively sealed (e.g. by welding or using adhesive) to upper major surface 28 of test strip 20 as described elsewhere herein. Upon movement (e.g. rotation) of separable distal portion 16 (e.g. by rotation of the U-shaped bendable frame forming the separable distal portion 16) in the direction of arrow B, removable portion 32 of the lower removable cover leaf 22 is also removed. Thus, the upper major surface 28′ of intermediate tip portion 14, which bears test components in a test area, is unsealed ready for use (step 2), whilst the opposing surface of intermediate tip portion 14 remains covered by cover leaf 25. Separable distal portion 16 may be rotated out of the plane of the remainder of the test strip 20 and used as a handle as described elsewhere herein.
Referring now to
In this and other embodiments, hinge portions 30′, 30 may simply be bendable portions of the upper removable cover leaf 21′ and/or lower removable cover leaf 22 and/or test strip 20 (between and/or part of proximal portion 12 and/or separable distal portion 16) or a hinge mechanism may be provided in one or more of these layers.
Embodiments of the invention can be envisaged in which separable distal portion 16 may be joined to proximal portion 12 of test strip 20 via a removable portion of a cover leaf, rather than being directly or indirectly connected via a test strip or being completely detachable. This and other arrangements in which separable distal portion 16 is not completely detachable facilitates subsequent replacement of the removable cover leaf and/or distal portion to cover up a used test area on intermediate tip portion 14.
Referring now to
In
In this example embodiment, the sample chamber 44 (which may be a capillary chamber) may extend into and terminate in separable distal portion 16′. Separable distal portion 16′ may be removed (in this case completely detached) by bending and breaking in the direction F about a longitudinal axis lying in the plane of the test strip from one short edge to another (in this an elongate test strip). In addition or alternatively the separable distal portion 16′ may be detached by bending and breaking test strip 20 in direction E about a lateral axis from one long edge to another.
The chamber forming the sample chamber is split open, with that portion of it lying in the intermediate tip portion 14 forming the actual sample chamber 44 for receiving sample and an open end 42 of the sample chamber being formed in a side wall (here along a short edge) of test strip 20. This will be described in more detail later in connection with
Referring to
Typically upper non-removable cover leaf 221 is an integral component having first and second (234A, 232) or first, second and third non-removable portions (234A, 232 and 234B) being formed from a single piece of material. The same applies to lower non-removable cover leaf 222.
Lower non-removable cover leaf 222 similarly comprises a first non-removable portion 334A extending over and fixedly attached to the lower surface of separable distal portion 16 of test strip 20, a second preferably non-removable portion 332 extending over and preferably fixedly attached to the intermediate portion 14, and also preferably a third non-removable portion 334B extending over and fixedly attached to proximal portion 12.
Upper first and second non-removable portions 234A, 232 may be frangibly connected to one another at lines of weakness therebetween (e.g. by utilising the kiss cutting method described elsewhere herein). Similarly the lower first and second non-removable portions 334A, 332 may be frangibly connected to one another at lines of weakness (e.g. by kiss cutting). Thus the upper and lower non-removable cover leaves 221, 222 are initially intact providing a seal over at least part or substantially all of the upper and lower major surfaces 28, 29 respectively and at least over the test area.
In one example embodiment, the upper second portion 232 may optionally not be attached to the intermediate portion 14 forming in effect a piercable removable portion 232, as will be described later. Intermediate portion 14 may be an intermediate tip portion as described elsewhere herein. Separable distal portion 16 may be a U-shaped frame as described elsewhere herein or may be rectangular or other shape attached to the intermediate portion 14 as described elsewhere herein. In step 1, a user has, preferably if appropriate, separated test device 500 from its neighbour(s) in a row. The user may insert the proximal end 12 into a meter (e.g. to engage exposed contacts 18).
The meter may comprise a protrusion (such as an elongate platform) (not shown) to engage the underneath of the proximal and intermediate portions 12, 14 of test strip 20 and associated lower third and second non-removable portions 334B, 332 of lower non-removable cover leaf 222
In step 2, gripping the meter (or proximal end 12, if the test device is not inserted in to the meter) in one hand, a user may depress the separable distal portion 16 of the test strip (typically by depressing the upper first non-removable cover portion 234A located thereon), causing the here U-shaped frame forming the separable distal portion 16 (and associated non-removable cover leaf portions 234A, 334A) to rotate downwards about hinge portion 30 in the direction of arrow B out of the plane of the remainder of test device 500.
During this step (step 2) the intermediate portion 14 remains in line with proximal portion 12. Also the upper first non-removable cover portion 234A breaks away from the upper second non-removable cover portion 232 on the intermediate portion 14. The second non-removable cover portion 232 remains on the intermediate portion 14.
Similarly, during step 2 the lower first non-removable cover portion 334A breaks away from the lower second non-removable portion 332 on intermediate tip portion 14. Thus the upper and lower major surfaces of the intermediate tip portion 14 remain covered (by non-removable portion 232 and 332 respectively), but the periphery of intermediate tip portion 14 is exposed.
Thus, a sample inlet port (not shown) provided in the periphery of intermediate tip portion 14 (either as an ‘end fill’ or ‘side fill’ inlet port) is exposed. A cut away notch forming a depression and/or a protruding nodule forming a protrusion may be provided in the periphery of intermediate tip portion 14 to indicate the location of the sample inlet port to a user.
In the embodiment in which the intermediate tip portion is not attached to the upper cover leaf portion 232 of the upper cover leaf 221, during step 2, the separable distal portion 16 is rotated downwards in the direction of arrow B causing the upper cover leaf portion 232 to rotate with the remainder of upper cover leaf 221 in the direction of arrow B. Thus, the intermediate portion 14, here an intermediate tip portion 14, (which does not rotate and is preferably supported on a platform on the meter) exerts an upward force on upper cover leaf portion 232 and pierces it causing it to break. The (now broken) upper cover leaf portion 232 travels downwards along with intermediate tip portion 14 in the direction of arrow B. Thus, intermediate tip portion 14 (its upper surface and its periphery) is exposed ready to receive a sample.
Typically, in either case, if a platform is provided on a meter adjacent to the strip port connector, the platform will approximately match the size and shape of the intermediate portion 14, when the strip is inserted into the strip port connector of the meter thus providing support to the intermediate portion 14 during the rotation of separable distal portion 16.
Referring to
Referring now to
Hydrophilic layer 80 may also be known as an anti-fog layer. Exposed contacts 18 are located on a proximal portion 12 of test strip 20. An intermediate portion 14 comprising test strip components (for example measurement electrodes, sample inlet port 42, sample chamber 44 and air vent 46) in a test area is provided. Typically, the measurement electrodes (here carbon pads 56 overlaid with reagent (such as a printed reagent layer or reagent pad 68)) are located on a lower floor of the sample chamber 44 with the sample inlet port 42 being at a distal end of the sample chamber and the air vent 46 being at a proximal end of the sample chamber.
In the example embodiment, the test strip 20 has junctions 72 (typically frangible portions of substrate 50 and/or removable cover leaf/leaves—see items 21 and 22 in
The intermediate tip portion 14 has on or within its perimeter an opening forming sample inlet port 42 in fluid communication with a sample chamber 44. Sample chamber 44 is in fluid communication with an air vent 46. Contacts 18 are capable of communicating with an external metering device.
Referring now to
The upper profiled seal 48/48′ is shaped preferably to completely surround the intermediate tip portion 14 without sealing to intermediate tip portion 14 to any appreciable extent. Nevertheless, the upper profiled seal may seal upper removable cover leaf 21 partially within the perimeter of the intermediate tip portion 14 (e.g. across cuts 36) as described elsewhere herein. Upper removable cover leaf 21 may for example be removably sealed to upper surface 28 in the region of its removable portion by provision of upper seal 48/48′ as a peelable seal, peelable adhesive or peelable weld (e.g. a thermal weld). Proximal portion 48′ of the upper profiled seal may have a pointed shape to facilitate the start of a peeling action. An unsealed tab portion 26 on upper removable cover leaf 21 is provided to aid removal of the removable portion of the upper removable cover leaf 21.
Referring now to
Having had upper and lower removable cover leaves 21 and 22 mounted thereon via respective seals 48 and 49 (which may be provided by separate adhesive layers or regions of thermal or chemical sealing of removable cover leaves 21, 22), a test device 100 comprising a now sealed test strip 20 is provided as shown in
Whilst the upper and lower removable cover leaves 21 and 22 cover, surround and protect the intermediate tip portion 14 from exposure to moisture in the atmosphere via major surfaces 28 and 29 of test strip 20, the edges of the test strip 20 about its perimeter 74 are not covered. Thus moisture may be absorbed into the test strip via this exposed perimeter. The inventors have appreciated that this is a limited route for introduction of moisture into the strip and such moisture introduction may be offset by use of removable cover leaves having moisture adsorbing properties and/or a supplementary carrying pouch which may have moisture adsorbing properties and/or other measures. Indeed, sealing across and partially within cuts 36 via one or both major surfaces may further impede moisture ingress by providing partially sealing of the side wall forming the periphery of intermediate tip portion 14 (having the test components).
The following describes how to use the test device of the invention. Rows of a limited number of connected test devices 10 (e.g. as in
A person may remove one or more test devices 10 from the row by holding the test device 10 to be removed in one hand and the remainder of the row of test devices in the other hand. A twisting or a pulling motion between the two hands breaks the junctions 72 between the devices 10 held in each hand so that the test devices 10 can be separated.
Referring now to
Next, while still holding the tab portion 26 of top cover 21 and/or the removable portion 32′ of top cover 21, top cover 21 can be used to provide a handle and additional leverage to bend the bendable frame (separable distal portion 16) back and away from the tip (intermediate tip portion 14).
The test device 100 in
The present invention advantageously enables the sample inlet port 42 to be made accessible by the bending of the bendable frame 16 away from the tip. Thus, a fluid sample can now be easily presented to the sample inlet port 42 in the end wall of the intermediate tip portion 14. The fluid sample is drawn into the sample chamber 44 by capillary action with chamber gases being vented through the air vent 46.
An assay is conducted on the fluid sample. When the assay is complete, the test device 100 can be removed from the external metering device by gripping the tab portion 26, and/or removable portion 32 of the top cover 21 and/or bendable frame (separable distal portion 16) and pulling the test device 100 out of the metering device.
There is an option to bend the bendable frame (separable distal portion 16) back into its initial position in which it surrounds the intermediate tip portion 14 so that top cover 21 can be laid across the upper major surface of the device so as to provide protection against touching any residual fluid sample adhered to exposed surfaces or the edges of the intermediate tip portion 14. The test device 100 is ready for safe disposal.
The following describes how to manufacture a test device. Referring to
A first series of carbon tracks 54 forming a first conductive layer 52 is disposed on a first major surface of base substrate 50. At one end conductive tracks 54 form carbon pads 56 which form part of the measurement electrodes. A second series of conductive tracks (silver tracks 58) form a second conductive layer 52′ disposed on and substantially covering part of carbon tracks 54. A first portion of the carbon tracks 54 is not covered by the silver tracks 58 forming the carbon pads 56 in a working area of the test strip 60. A second portion of the carbon tracks 54 is not covered by the silver tracks 58 forming the electrical contacts 18 that communicate with an external metering device.
An electrically insulating layer 62, formed of e.g. dielectric material, is disposed on first (here upper) major surface of the base substrate 50 and substantially covers the carbon/silver tracks 54, 58. A first portion of the carbon tracks 54 defined by insulation window 64 is not covered with insulating layer 62 completing the definition of the test strip working area. The contacts 18 are not covered with insulating layer 62. An adhesive layer 66 is disposed on and partially covers the insulating layer 62 and substantially surrounds the working area of the test strip 60. Adhesive layer 66 is U-shaped to avoid blocking access to the working area within insulation window 64.
A reagent layer 68 disposed on the adhesive layer 66 and substantially covers the working area within insulation window 64. The completed substrate with printed layers 60 is seen in
A first series of cuts 90A are made through the thickness of the printed base substrate 60 defining the perimeter 74 of and a series of junctions 72 of base substrate 50 are not cut so that each printed base substrate 60 remains connected to its neighbour. These cuts 90A may be made before or after printing on base substrate 50 to form printed base substrate 60 with printed layers.
A second series of cuts 36A through the thickness of the base substrate within the perimeter 74 partially surrounds the carbon pads 56 in the working area to define the base substrate portion 14A of a sample application tip (intermediate tip portion 14) and the base substrate portion 16A of a bendable frame (separable distal portion 16) substantially surrounding the intermediate tip portion 14A.
First and second series of cuts 90A, 36A may be formed simultaneously or one preceding another. Lines of weakness 30A may be provided in base substrate 50 to provide hinge portions between the laterally spaced side arms of the bendable frame (separable distal portion 16A) and the proximal portion 12A bearing contacts 18.
Next, a second sheet-like insulating substrate material of about 50 mm wide by about 1 kilometre in length by 0.100 mm thick is provided to from a spacer layer 70 (see
A second series of cuts 36B through the spacer layer within perimeter 74B defines the spacer portion of a sample application tip (intermediate portion 14B) and the spacer portion of a bendable frame (removal distal portion 16B) substantially surrounding the intermediate tip portion 14B.
A third series of cuts through the spacer layer within the perimeter 74B of the intermediate tip portion 14B creates a hole or void defining the spacer portion of a sample chamber 44. Sample chamber 44 may be pre-formed in the spacer layer rather than being cut on the fly.
Next, a third sheet-like insulating substrate material of about 50 mm wide by 1 kilometre in length by 0.100 mm thick is provided to form a hydrophilic layer 80 (also known as an anti-fog layer). The hydrophilic layer 80 comprises a hydrophilic coating (not shown) disposed on a major surface of hydrophilic layer 80 facing the test area defined by sample chamber 44 and insulation window 64. The hydrophilic layer 80 may also comprise an adhesive or heat activated binding polymer coating disposed on a second major surface (facing outwards). A first series of cuts 90C defines the perimeter 74C with a series of junctions 72 remaining so that each test strip portion of spacer layer remains connected to its neighbour.
A second series of cuts 36C may be made within the perimeter 74C to define the anti-fog portion of a sample application tip (intermediate tip portion 14C) and the anti-fog portion of a bendable frame (separable distal portion 16C) surrounding the intermediate tip portion 14C.
A third series of cuts may be made through the antifog layer to create a hole or void within the perimeter of the tip defining the sample chamber air vent 46. Air vent 46 may be pre-formed in hydrophilic layer 80. Indeed, first, second and third series of cuts may be pre-formed in base substrate 50, spacer layer 70 and/or hydrophilic layer 80 rather than being cut on the fly.
The outer facing major surface of the spacer layer 70 (for example with the adhesive) is bonded to the inner facing major surface of the hydrophilic layer 80 in register such that: the rectangular cut-out or void of the spacer layer defines the width of the sample chamber 44; the air vent 46 on the hydrophilic layer 80 lies at one end of the sample chamber 44 (typically the proximal end); the outer perimeters 74B, 74C of the spacer layer 70 and hydrophilic layer 80 match when these are laminated; the junctions 72B, 72C on the spacer layer 70 and hydrophilic layer 80 are of the same geometry so that these match when these are laminated; and the spacer layer and hydrophilic layer tip portions 14B and 14C are similarly sized and shaped so that these match when these are laminated.
Next, the upper major surface 28 of the printed base substrate 60 is bonded to and is substantially covered by the spacer layer/hydrophilic layer laminate to form a test strip 20 such that: typically, these are of substantially the same size and are in register so that: the contacts 18 are not covered; the sample chamber 44 is fully defined; the perimeter 74A on the base substrate with printed layers 60, that defines the test strip width, matches the perimeter 74B, 74C of the spacer/hydrophilic laminate; the geometry of the intermediate tip portion 14A on the printed base substrate 60 matches the geometry of the intermediate tip portion 14B, 14C on the laminate and the bendable frame 16 that surrounds the intermediate tip portion 14 is fully defined from portions 16A, 16B and 16C.
Referring now to
Optionally, upper removable cover leaf 21 is a laminate such as a triple layered laminate and may comprise a durable plastic as an outside facing layer, a thermo-formable material that may have a desiccant material as part of its structure as an inside facing layer (facing inward towards test strip 20) and a high moisture barrier film between the outside and the inside facing layers. Preferably, the inside facing surface of the upper removable cover leaf 21 is laminated to a first major surface 28 of the test strip 20 so that the inside facing layer of the upper removable cover leaf 21 comes into contact with major surface 28 of the test strip. Furthermore, preferably the upper removable cover leaf 21 optionally completely covers the first major surface 28 of the test strip and extends to substantially or completely cover the exposed carbon electrode contacts.
Optionally, a tab 26 may remain unsealed to but nominally extends over proximal portion 12 in the region of contacts 18.
As an alternative to a separate adhesive layer to hold removable cover leaf 21 in place, a profiled heat seal may be used. Thus a next step may include applying a profiled heat seal so that: an area of the upper removable cover leaf 21 is selectively sealed to an area 48 of the test strip 20 such that the bendable frame (separable distal portion 16) is substantially sealed to the top cover leaf 21; the intermediate tip portion 14 is partially sealed to the top cover and is completely surrounded by a seal; and the profile of the seal is designed to facilitate peeling of the upper removable cover leaf 21 off the test strip 20 (for example, a reduced seal or non-existent seal in the region of removable portion 32′). Preferably, the profile and/or heat seal process parameters are such that the upper removable cover leaf 21 remains attached by a portion 34′ to the bendable frame (separable distal portion 16) of the test strip 20.
A fifth sheet-like insulating substrate material of about 50 mm wide by 1 kilometre in length by 0.150 mm thick is provided to form bottom cover 22 (lower removable cover leaf 22). Typically, this is a multi-laminate material with moisture barrier properties and/or moisture adsorption properties and structure as described above in connection with the upper removable cover leaf 21. Thus, an inside facing surface of the lower removable cover leaf 22 is laminated to a second major surface 29 of the test strip 20 so that the inside facing layer comes into contact with lower major surface 29 of the test strip 20, preferably completely covering it.
A next step (if a separate adhesive layer is not used) may be applying a profiled heat seal 49 so that an area 49 of the bottom cover is selectively sealed to an area of the test strip 20 so that: the bendable frame (separable distal portion 16) is substantially sealed to the lower removable cover leaf 22; the intermediate tip portion 14 is not sealed (or not sealed to any appreciable extent) to the removable cover leaf 22 (in the region of removable portion 32), and the intermediate tip portion is completely surrounded by a seal.
A series of cuts 90D through the upper/lower removable cover leaves 21 and 22 define their perimeters 74′/74″ with substantially the same geometry as the perimeter 74 (74A, 74B,74C) defined by cuts on test strip 20. Optionally one or more cuts 90A, 90B, 90C and 90D may be formed at the same time, for example, after formation of a packaged test device 10, 100, 200, 300, 400.
Finally, a card of packaged test devices 10, 100, 200, 300, 400 (see for Example
The bendable frame (separable distal portion 16) provides a sealing platform for the upper removable cover leaf 21, 21′, 22. In particular, the bendable frame (separable distal portion 16) bends out of the plane of the test strip 20 and enables the manufacture of a test device 10 with an end fill sample chamber. In another embodiment there may be (not illustrated) a sample inlet port or an upper major surface of the test strip which provides for a top fill type sample chamber. The tab 26 (of the upper removable cover leaf 21) provides for an easy means to peel the top cover away from the intermediate tip portion 14. Furthermore, the upper removable cover leaf 21 is strongly sealed or welded to the portion of the bendable frame (separable distal portion 16) adjacent the sample inlet port 42 which means that the upper removable cover leaf 21 remains an integral part of the test device so that the tab 26 and peeled back top cover (removable portion 32′) can be used as a handle to hold the strip and/or a handle to pull the strip out of an electronic device and/or a handle to assist in bending back the bendable frame (separable distal portion 16) and/or a way of covering the used test strip for clean disposal and therefore this improves the ease of use of access to individual test strips.
Referring to
Furthermore test device 200 comprises upper and lower removable cover leaves 122, 124 respectively.
Initially, proximal portion 12, intermediate portion 14′ and separable distal portion 16′ form an integral component, here being formed from the same test strip 20. However, as in other embodiments of the invention, two or more of the three portions (for example two or more of the three portions of the test strip 20 or of the underlying base substrate 60) may be formed separately and joined together in an appropriate manner to provide integrated test device 200.
Here, preferably the periphery of intermediate portion 14′ forming a long edge of test strip 20 is in line with the periphery of proximal portion 12 forming a long edge of test strip 20. Thus, in contrast with the embodiment shown in
Cuts 130 are formed part way across the width of test device 200 from each long edge towards a test area 27 comprising test components as described elsewhere herein but stopping short of the test area 27. These cuts 130 may be pre-formed in test strip 20 and/or upper and/or lower removable cover leaves 122 and 124 or these may be formed in these once test device 200 is assembled, (although preferably these are formed prior to singulation into individual test devices or separation into a small row of test devices).
Upper removable cover leaf 122 (described below as top cover 122) comprises a removable portion 132 peelably covering the test area 27, a non removable portion 134A fixedly attached to separable distal portion 16′ and a further non-removable portion 134B fixedly attached to the intermediate portion and the proximal portion and. Removable portion 132 of upper removable cover leaf 122 extends over and surrounds the test components, sealing these in respect of the upper surface of the test device 200 from moisture ingress. Upper removable cover leaf 122 also preferably comprises a non removable portion 134B covering much of the remainder of test strip 20. Optionally, non removable portion 134B can be dispensed with and the removable portion 132 of upper removable cover leaf 122 may extend to cover and seal only test components or may extend beyond to seal at least part of or substantially all of the upper surface of test strip 20, although contacts 18 may be left exposed.
One embodiment of the test device 200 construction is as follows. A printed substrate layer 60 with printed electrochemical layers is formed, including a reagent pad 68 on a base substrate 50. A combined spacer/hydrophilic layer 70/80 defines a sample chamber 44 and preferably substantially covers the upper major surface of the printed substrate layer 60 of test strip 20, although preferably it does not cover contacts 18. A bottom cover 124 (lower cover leaf 124) with moisture vapour barrier properties preferably completely covers the underside of the substrate layer of test strip 20. A top cover 122 with moisture vapour barrier properties, preferably completely covers the upper major surface of spacer layer 70/80.
Also in a preferred embodiment of this aspect of the invention, a further important feature of the test device 200 is that the top cover 122 is divided into two sections (a first section comprising removable portion 132 and non-removable portion 134A and a second section comprising non-removable portion 134B (either pre-formed as separate two sections or cut at 130A to form two sections in an integral cover leaf, or provided with lines of weakness at 130A). This allows for the section (removable portion 132 and non-removable portion 134A) of the top cover 122 that covers (here directly covers) the sample chamber 44 to be removed (along with separable distal portion 16) to expose the chamber visually to the user and for the air vent 46 at the end of the sample chamber to be exposed physically to allow sample chamber gases to be vented when fluid sample is being introduced into to the chamber. The sample chamber opening (sample inlet port 42) may be provided in the hydrophilic layer, (similar to air vent 46) to provide a ‘top fill’ sample inlet port, in which case this would be exposed upon removal of removal cover portion 132. Alternatively the sample inlet port 42 may be provided in a side wall along a long edge (“side fill”) or preferably a short edge (“end fill”) of test strip 20 as shown in the Figures.
The sample chamber opening (sample inlet port 42) is covered (albeit it is not in direct contact with top cover 122) by top cover 122 and is also exposed physically, when the twist off cap (separable distal portion 16′) is broken off and removed along with removable portion 132.
In a preferred embodiment, the top cover 122 can be constructed or processed such that the robust outer material of the multi-laminate thin film forming the top cover 122 is cut but not the middle moisture barrier (e.g. aluminium layer) and/or not the inner facing tie (e.g. thermoplastic layer) although the inner facing thermoplastic layer may also be cut. Thus top cover 122 is provided with lines of weakness (here cuts 130A) to facilitate it breaking into two sections (a first section comprising removable portion 132 and non-removable portion 134A and a second section comprising non-removable portion 134B). The profile of cuts 130A can be matched with the portion of test device required to be exposed when the twist off cap is separated from the test device. The moisture barrier properties of the top layer 122 are not affected because the moisture barrier layer of, for example, aluminium is not cut. This method of cutting material is known as kiss cutting.
The lower cover leaf 124 (described below as bottom cover 124) can be, for example, a multi-laminate thin film material whereby a moisture barrier layer such as aluminium is sandwiched between a robust outer layer of plastic exposed to the outside environment and an internal tie layer such as adhesive or thermoplastic that binds to the substrate layer 50. The top cover 122 can be the same material as the bottom cover. Top cover 122 may completely cover the chamber layer.
The substrate layer 50 can be formed, for example, from a continuous web of a heat stable polyester that can be continuously printed reel to reel to lay down and dry several important electrochemical layers such as conductive layer(s) 52, 52′ including contacts 18, an insulation layer 62, and a reagent layer 68 in the form of a pad containing the reagent mixture that is placed to form a reaction zone within insulation window 64 on the intermediate portion 14′ of the test strip 20.
A spacer layer 70 defines a channel with capillary action properties. This channel is placed directly over the reaction zone of the intermediate portion 14′ creating a sample chamber 44. An air vent 46 (here a rectangular air vent to aid registration with the chamber 44 during manufacturing) is cut through the thickness of a hydrophilic layer 80 at one end of this channel allowing sample chamber gases to be vented when sampling fluid to do a test. Preferably in one important embodiment, the channel extends from the intermediate portion 14′ into the twist off cap component forming separable distal portion 16′.
Preferably the separate layers 124, 60, 70, 80, 122 are brought together in a continuous reel to reel process from reel stock to produce a single web construction. An example section of a completed web of test devices 200 is shown in
A cap forming step can be introduced whereby material is cut away at 130 between the twist off cap portion (separable distal portion 16′) and the sample testing portion (here formed by proximal portion 12 and intermediate portion 14′ of the test device 200). This feature provides a good visual cue to the user to distinguish between the portions of the test strip. The cuts outs formed by cuts 130 can also be designed in such a way as to facilitate twisting off the cap portion (separable distal portion 16′) and separating it from the remainder of the test device by creating a weak point in the test device 200. The narrow neck formed by cuts 130 between intermediate portion 14′ and separable distal portion 16′ forms a region of weakness in test device 200.
In a preferred embodiment a feature of the invention is that the channel defining the sample chamber 44 extends from the sample testing portion (specifically form the intermediate portion 14′) of the test device 200 into the twist off cap portion (separable distal portion 16′), see
When the twist off cap (separable distal portion 16′) is separated from the remainder of the test device 200 it results in the creation of an opening 42 in the channel to the outside environment which allows entry of the fluid sample to be analysed, thus forming the sample inlet port 42.
A preferred embodiment of one aspect of the invention is described in which the end user receives a block of individually packaged test strips attached together as shown in
The block can be any number of test strips but it is preferred to supply blocks of between 5 and 100 strips. A test strip can be singulated from the block by twisting or breaking the strip away from the block in one easy step. This can be facilitated by including perforations or cuts between test strips.
Test strips 20 are packaged individually to protect them from moisture vapour while providing a simple, easy to open, solution to access the test strip to do a test.
In various aspects, the invention provides a means to open the test strip to create an opening to a sample chamber, a means to visually expose the sample chamber and to physically expose an air vent in one easy step. Furthermore, aspects of the invention provide a way of integrating a cap forming process into a reel to reel lamination process to form a break and/or twist off cap.
Furthermore aspects of the invention provide individually packaging of the test strips in such a way that may leave exposed the printed electrical contacts of the test strip contacts with a meter. In various example embodiments, the invention provides packaging configurations that improve protection of each strip individually from the effects of moisture and/or reduces the cost and complexity of manufacture and/or improves the ease of use of accessing individual test strips.
The present invention provides individually packaged test strips that are easy to open while providing an efficient and cost effective method of mass production.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1304348.4 | Mar 2013 | GB | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2014/054600 | 3/10/2014 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 61775828 | Mar 2013 | US |
