Technical Field of the Invention

The present invention relates to a cartridge for test apparatus, to test apparatus including such a cartridge and to a method of testing a sample. The invention is particularly, although not exclusively, concerned with apparatus for testing urine to determine pregnancy and/or ovulation.

Background to the Invention

An existing type of apparatus for ovulation testing comprises test sticks used with an electronic reader. Test sticks are supplied in sealed packs. Each stick comprises a housing holding an absorbent sampler strip which projects from the stick and is covered by a removable cap.

To use the apparatus a test stick is removed from its pack, the cap removed to reveal the sampler strip and the test stick partially inserted into the reader so that part of the stick and the sampler strip is exposed. A urine sample is then applied to the sample strip.

The sample strip is arranged to produce a detectable change, depending upon characteristics of the urine sample, and the reader is arranged to measure this change and display the result to a user via a display screen.

Characteristics of the sample strip are such that, to obtain an accurate result, the test stick must be inserted, and correctly inserted, into the reader before a urine sample is applied. It must also be kept free from contamination before use. In practice problems can arise with this apparatus where a user contaminates the sample strip before use and/or applies a urine sample before introducing the test strip into the reader. This can result in the reader delivering an inaccurate reading.

Embodiments of the present invention have been made in consideration of these problems.

Summary of the Invention

According to an aspect of the present invention there is provided a cartridge for test apparatus, the cartridge being arranged to receive a sample to be tested and to releasably engage with a reader to enable a sample received by the cartridge to be analysed, wherein the cartridge comprises a movable cover arranged to cover a part of the cartridge at which a sample to be tested is received and a latch means arranged to prevent the cover being moved to expose the part of the cartridge at which a sample to be tested is received unless the cartridge is engaged with a reader,

Thus, the latch prevents a user from uncovering the part of the part of the cartridge at which a sample to be tested is received such as, for example, a sample strip or some other sensor element, unless the cartridge is engaged with a reader.

The cartridge may be or comprise a test stick or other sensor elelment. The cartridge may comprise a housing to which a sensor element, such as a test stick, is mounted. The moveable cover may be arranged to engage with part of the housing to cover part of the sensor element. Another part of the housing may be arranged to engage with a reader. Part of the sensor element may be arranged to engage with a reader. The sensor element may be mounted to the housing so that, when the housing is engaged with a reader, part of the sensor element is engaged with or positioned relative to the reader so that the reader can obtain information relating to a sample which has been applied to the sensor element.

The cover may be removable. In this case the !atch may prevent the cover being removed unless the cartridge is engaged with a reader. The cover may be a cap.

The latch may comprise mutually cooperating formations formed on the cover and remainder of the cartridge respectively.

In one embodiment the latch comprises a protrusion formed on one of the cover or the remainder of the cartridge and an aperture or recess on the other of the cover or remainder of the cartridge. The protrusion may be resiliently biased and may be wedge shaped.

The cartridge may comprise a test strip, or other sensor element, for receiving a sample. In this case the cover may cover at least part of the test strip.

According to another aspect of the present invention there is provided test apparatus comprising a reader cartridge as described above, with or without any of its optional features, wherein the reader comprises a release means arranged to release the latch when the cartridge is engaged with the reader.

The release means may comprise a formation arranged to contact one or more components of the latch when the cartridge and reader are engaged. The formation may be arranged to urge a protrusion of the latch through an aperture when the cartridge and reader are engaged. The apparatus may be for testing a liquid. The liquid may be urine, blood or saliva. The apparatus may be arranged to detect pregnancy and/or ovulation.

The apparatus may comprise a plurality of cartridges. Each cartridge may be supplied in a sealed package.

According to another aspect of the present invention there is provided a method of testing a sample, the method comprising: providing a cartridge for test apparatus according to the first aspect of the invention, with or without any of its optional features; providing a reader for analysing a sample received by the cartridge; engaging the cartridge with the reader, thereby releasing the cover; moving the cover to expose a part of the cartridge for receiving a sample; and applying the sample to be tested to the exposed part of the cartridge.

Detailed Description of the Invention

In order that the invention may be more clearly understood an embodiment thereof will now be described, by way of example only, with reference to the accompanying drawings, of which:

Figure 1 is a perspective view from above of a reader and cartridge of test apparatus;

Figure 2 is a perspective view from above of the apparatus of figure 1 with the cartridge and reader engaged with each other; Figure 3 is a plan view of the apparatus of figure 2 with a cap removed from the cartridge;

Figure 4 is a perspective view from below of the apparatus of figure 1 ;

Figure 5 is a simplified cross-sectional view of part of the cartridge of the test apparatus of figure 1 ;

Figures 6 to 8 are simplified cross- sectional views of part of the cartridge of the test apparatus of figure 1, and part of the reader of figure 1, showing the cartridge separate from, partially introduced into and fully engaged with the cartridge; and Figure 9 is a perspective view of part of an inside surface of the cartridge.

Referring to the drawings there is shown test apparatus for analysing urine, or other liquid, samples. The tester is particularly intended for analysing a urine sample for the purposes of pregnancy or ovulation testing, but it could be used for making other tests.

The apparatus comprises an electronic reader 1 and a cartridge 2 having a cap 3.

The cartridge comprises a moulded plastics body comprising a moulded plastics support 4 supporting a test strip 5. The test strip 5 is for receiving a urine sample and providing a detectable change to indicate a property of the sample, such as, in the case of a pregnancy test strip, the concentration of human Chorionic Gonadotrophin in urine. Test strips, sticks and other test or assay apparatus are well known in the art and so need not be described in further detail. Any suitable sensor element could be used in place of the test strip 5 shown. The test strip 5 is supported in the cartridge so that it extends from opposite ends of the cartridge.

The cartridge 2 is provided with a moulded plastics cap 2. The cap 2 fits snugly over one end of the cartridge with a close sliding fit. When fitted, the cap encloses the test strip 5 extending from that end of the cartridge ^' .

The electronic reader 1 comprises a moulded plastics body. The body is configured to engage with the opposite end of the cartridge 2 to the cap 3 with a snap fit. The body comprises an interface portion 6 which, when the cartridge and body are engaged with each other, extends into the cartridge and receives the test strip 5. Resiliency flexible formations 7 are provided on an inside surface of the body of the cartridge 2 which capture a part of the interface portion 6 of the body of the electronic reader, causing the reader and the cartridge to releasably engage with each other with a snap fit. The body of the electronic tester houses electronic components and circuitry arranged to read a test strip 5 of a cartridge 2 engaged with the tester, and to display a result to a user via an LCD screen 8. Electronic readers are known, and so will not be described in further detail here.

Referring in particular now to figures 5 to 8 the cartridge 2 and cap 3 are respectively provided with mutually cooperating components of a latch, operative to prevent removal of the cap 3 from the cartridge 4 unless the cartridge 2 is engaged with the electronic reader 1. The latch comprises a wedge-shaped protrusion 9 formed on the inside surface of an elongate projection 10 to the wall of the cap 3. The thin end of the wedge faces out from the opening into the cap. Owing to the material from which the cap is moulded the projection is resiliently flexible relative to the remainder of the cap. The latch further comprises an aperture 11 in an indented region of the outside of the cartridge 2 over which the cap fits, spaced from the edge of the cartridge. As the cap 3 is fitted over the cartridge 2 the wedge shaped protrusion contacts the outside of the cartridge causing the elongate projection to the wall of the cap to flex outwards allowing the protrusion to ride over the cartridge until it snaps into the aperture 1 1 allowing the protrusion 10 in the wall of the cap to return to its original state. If the cap is urged away from the cartridge the thick end of the wedge shaped protrusion will bear against the edge of the aperture 1 1, preventing removal of the cap from the cartridge.

The interface portion 6 of the electronic reader 1 comprises a formation, in the form of an elongate fin 12, arranged so that as the cartridge and the reader are engaged the fin is urged into contact with the thin end of the wedge shaped projection 9 of the cap. This urges the wedge shaped projection back though the aperture 1 1 in the cartridge to a position, shown in figure 8, where the protrusion no longer prevents the cap from being withdrawn from the reader 1. When the cartridge and reader are engaged, the fin extends through the formations which engage the cartridge and reader with a snap fit and is accommodated in a groove 13.

It will be appreciated that the latch may be implemented in a variety of different ways whilst still providing the same functionality, For example a protrusion on the cartridge could be received into an aperture or recess in the cap. Cartridges are supplied with a cap fitted. They must therefore be engaged with a reader before the cap can be removed to enable a urine sample to be applied to the test strip. It is therefore impossible for a sample to be introduced to the test strip without the cartridge being engaged with a reader. This eliminates, or at least substantially reduces, the risk of a test strip being incorrectly read as a result of the test strip being contaminated before use, or coming into contact with a sample before being monitored by the reader.

The above embodiment is described by way of example only. Many variations are possible without departing from the scope of the invention as defined in the appended claims.