Patent Publication Number: US-2021186390-A1

Title: Integrated blood test device

Description:
TECHNICAL FIELD 
     The present invention relates to devices and methods for conducting blood tests using an integrated testing device. 
     BACKGROUND OF THE INVENTION 
     Blood tests have conventionally been conducted by drawing blood, for example by venepuncture, and submitting blood for testing to central pathology facilities. Increasingly, there is a demand for tests to be undertaken and interpreted at the point of care, and for self-tests where the user takes their own blood, submits it to a local test device and reads the test outcome. 
     Advances in the structure, chemistry and biochemistry of test materials have produced the possibility to extend self-testing to a much wider group of users and conditions, particularly where the potential exists for relatively rapid tests. Tests have been developed to allow for testing for many indications, for example various pathogen, antibodies, blood components, biochemical markers, and other substances. 
     The present applicant has filed applications directed at various aspects of integrated test units, including for example WO/2012/048388, WO/2011/113114 WO2015075677, and PCT/AU2016/051134, the disclosures of which are hereby incorporated by reference. 
     There is a need for further refinement in such devices, for example in relation to facilitating self-testing. Self-testing presents a very specific set of design challenges, relative to tests intended for professional or regular users. The user will often not have regular, or even any, experience in conducting such tests. Thus, the risk that errors will be made, which in turn undermine the quality of the outcome, is significant. 
     It is an object of the present invention to provide integrated testing devices which are reliable and reduce the risk of errors by the user. 
     SUMMARY OF THE INVENTION 
     In first broad form, the present invention provides a device in which test fluid and blood are delivered to a test material by a single actuator. 
     According to one aspect, the present invention provides an integrated test unit including a blood collection recess, a test component, and a reservoir containing test fluid, the blood collection device operatively delivering blood to the test component once actuated, wherein an actuator causes the blood to be delivered to the test component and causes the test fluid to be released from the reservoir in order to contact the test component. 
     According to a further aspect, the present invention provides an integrated test unit, including a blood collection device and a test component, the test component including one or more visual indications relevant to the test outcome or status, wherein the blood integrated test unit includes a transparent window over the or each visual indication. 
     According to a further aspect, the present invention provides an integrated test unit including a blood collection recess, a test component, and a reservoir containing test fluid, the blood collection device operatively delivering blood to the test component once actuated, and an integrated lancet, wherein the actuator is located at a first location on the device, and the lancet is located at another location on the device. 
     According to another aspect, the present invention provides an integrated test unit, including a blood collection unit having a blood collection recess, the recess being adapted to directly receive blood from a user, a test material, and an actuator, wherein when the actuator is activated, the blood collection unit pivots to deliver blood to the test material. 
     According to another aspect, the present invention provides an integrated test unit, including a blood collection recess, the recess being adapted to directly receive blood from a user, the recess including a channel which operatively progressively fills with blood, such that when the channel is full it provides a visual indication to the user that sufficient blood has been received to conduct a test. 
     Suitable implementations of the present invention accordingly allow for easily used devices, particularly for self test applications, which facilitate 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Illustrative embodiments of the present invention will now be described with reference to the accompanying drawings, in which: 
         FIG. 1  shows an isometric view of one implementation of the present invention; 
         FIG. 2  is an exploded view of the components of the implementation of  FIG. 1 ; 
         FIG. 3A to 3D  are cross-sectional views of a device at various stages of operation; 
         FIG. 4  is a detailed isometric view of the blood collection unit; 
         FIG. 5  is a detailed cross sectional view illustrating the catch operation for the activation button; 
         FIG. 6  is a view of the blood collection unit from the opposite end to  FIG. 4 ; 
         FIG. 7  is a detailed cross-sectional view illustrating the pivot of the blood collection unit; 
         FIG. 8  is a view, partly in section, illustrating the operation of the interlock member before the lancet is actuated; 
         FIG. 9  is a view similar to  FIG. 8 , showing the interlock after lancet actuation; and 
         FIGS. 10 and 11  illustrate a fluid unit, in a full and discharged condition. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention will be described with reference to a particular implementation. It should be understood that the implementation discussed is purely illustrative, and is in no way limitative of the scope of the inventions disclosed. Various inventive features are disclosed, and it will be understood that this disclosure includes them in the combination as discussed, as well in in their individual integers and in sub-combinations. 
     It should be appreciated that the present invention in one form extends to a complete test device, including a test material, such as a test strip. The test material may be in any form and may be intended to be read by the user either directly, for example via conventional line indications, or using an automated or partly automated reading device. The examples described relate primarily to a conventional lateral flow test strip, however, the invention may be employed with alternative test materials, for example other strip based tests, or electronic sensors. The present invention is not limited to any particular test, condition, test approach or test reading process. Aspects of the present invention are concerned, rather, with various usability, mechanical and fluid handling aspects, not the biochemistry or other aspects of the test material as such. 
     However, the present invention also extends to a device which does not include the test material, but is adapted to do so. Where the context admits, the description and claims should be read to include both a device with a test strip or other material in place, and a device in which the test strip or other material has not yet been inserted. Thus, the present invention extends to both devices with an integrated test material, and devices which have yet to have a test component inserted. 
     The present invention contemplates that a test fluid is dispensed onto the test material. This may be a suitable buffer, or any other fluid which it is desirable or necessary to dispense onto the test material, in order to facilitate the test. It will be appreciated that the nature and volume of test fluid will be dependent upon the test to be performed, and it is anticipated that the nature of the test fluid and volume will be selected to complement the intended test and test material. In some cases the test fluid may be an active component of the test, and not merely a buffer or carrier. 
       FIG. 1  illustrates a device  10  according to one implementation of the present invention. It includes an upper shell  30 , lower shell  20 , blood collection unit  50  with blood collection recess  51  and channel  52 . Device  10  further includes actuator  60 , lancet mechanism  40  with cap  41 , and result window  70 . 
     The operation of the device, from perspective of the user, will now be described. This will be in the context of a self-test situation. However, it will be appreciated that many of the features and advantages of the illustrated device are also advantageous in point of care or other applications, and the scope of the invention includes self tests, professional use and point of care applications. 
     First, a user washes their hands, ideally with warm water to increase blood flow, and massages the selected finger for 10 seconds. The user then removes the lancet cap  41 , by twisting and pulling. The user then presses hard on the exposed lancet mechanism  40 . This releases a biased lancet which penetrates the user&#39;s finger, and then retracts within the housing of mechanism  40 . 
     The user then milks the finger, so as to produce droplet of blood. Typically, 5 to 20 μl are required. The user places their finger against the blood collection recess  52 , so that blood is collected. The blood flows into the recess  52 . This provides a visual indication to the user that sufficient blood has been delivered to provide a valid test. 
     The next step is to depress actuator  60 . As will be explained in more detail, until the lancet has been operated, an interlock prevents the actuator from being depressed. Activating the actuator causes the blood collection unit  50  to pivot slightly downward, so that the channel  52  contacts the test material  80  (not visible here) and the blood is delivered. At the same time, actuator  60  also depresses a reservoir of test fluid  100  (not visible here) and this is also delivered to the test material  80 . A latch mechanism hold the actuator in the engaged position, so that the fluid is delivered. 
     A further feature of device  10  is the result window  70 . Conventionally, a window is provided in a test device to show two indicator lines, for test outcome and a control line to indicate that the test is valid. These are conventionally open. According to the present implementation, a solid, partly transparent cover is provided over the test and control indicators. This prevents the user inadvertently putting the blood sample into the wrong opening. After the period appropriate for the test, the test and control lines are visible through the results window  70 . 
     The structure and mechanism of device  10  will be further understood by reference to  FIG. 2 . Lower shell  20  includes various lugs and location features, including an opening  21  for the lancet mechanism  40 . Next is the interlock  90 , whose operation will be described below in more detail. 
     Lancet mechanism  40  is conventional in operation, and any suitable lancet mechanism could be substituted as will be apparent to those skilled in the art. Lancet  42  is biased by spring  43 , so that when lancet housing  45  is sufficiently depressed relative to device  10 , tabs break away and the lancet  42  projects and then return spring  47  retracts it for safety. Safety cap  44  is increased in usability by the addition of safety cover  41 , formed as halves  41 A,  41 B. 
     Next in the assembly is strip carrier  85 , on which strip  80  rests in use and is retained in the correct position for testing, using retainer  86 . 
     Next is blood collection unit  50 , including lug  56  and spring  55 , which allow for the positive operation of the pivot function when the actuator is released, as will be described below. 
     Results window  70  as discussed above is transparent, so that the control and test lines can be seen. Preferably, the housing adjacent to the results window has markings of T and C adjacent to the potential results lines, indicating test and control. 
     Actuator  10  also compresses plate  75 , which in turn compresses test fluid test fluid reservoir  100 , not shown in this illustration, against surface  87 . Upper shell  30  includes actuator  60 , forms with a live hinge  61  to allow it to pivot downwards. 
       FIGS. 3A, 3B, 3C and 3D  illustrate the operation of the various components of device  10 , in cross section, at different points of operation of device  10 . It is important to understand that the device described is a single use device, intended for a single test. Once the device has passed a stage in operation, for example the lancet has been fired, then it is not possible to return to an earlier stage and re-use the lancet. 
     In  FIG. 3A , the device is as supplied, ready for use. The safety cap  44  is in position and lancet  42  has not been operated. Blood collection unit  50  is positioned so that its lower edge  53  is not in contact with the test strip  80 . Reservoir  100  is filled with test fluid, for example buffer or any other fluid required to facilitate the test. Actuator  60  is not depressed. The interlock member  90  is located engaged with the lancet mechanism  40 , and is slidable on the lower shell  20 . At this stage, it is in the (in this view) left hand position, and the lock posts  91  are positioned to engage actuator posts  66  (not visible here, see  FIG. 9 ). Thus, the user is prevented from depressing the actuator, and so neither blood nor test fluid can be delivered to test strip  80 . 
     As a result, the user has limited opportunities to make erroneous use of the device. The accompanying instructions next tell the user to remove the safety cap  44 . 
       FIG. 3B  illustrates device  10  with the safety cap  44  removed. The lancet is now ready for use. At this stage, nothing else in the device is altered. The user presses front surface  45  against the prepared finger, the lancet  42  fires, penetrates the finger, and retracts into the lancet mechanism  40 . This is the situation shown in  FIG. 3C . 
     The lancet mechanism is now in the retracted state, with front surface  45  moved back into lower shell  20 , and the lancet  42  safely stored. Additionally, the retraction has pushed interlock member  90  to the right, and so moved lock posts  91  (only one is visible) to the right, so that they no longer prevent the movement of actuator  60 . 
     The user at this stage should produce a droplet of blood, and place it into contact with blood collection recess  51 . The user receives a visual indication that sufficient blood is provided when groove  52  is filled. Device  10  is now ready for the actuator to be depressed. 
     It is important to understand the mechanism of the blood collection unit. It is as this stage captured in a locked, upward position, biased by spring  55  on lug  56 . It is also, via transverse section  58 , captured in groove  36  of latch  35 . Thus, at this stage the blood collection unit  50  is held away from contact with test strip  80 . This can be seen in more detail in  FIG. 5 . A more detailed view of blood collection unit  50  can be seen in  FIG. 4 . 
     The user next depresses actuator  60 . This has several consequences. The reservoir  100  is located directly under the actuator, so as to be depressed and the test fluid discharged into well  101  for discharge via opening  102  onto test strip  80 . Thus, test fluid is discharged onto the test strip  80 . 
     The actuator moving down also releases transverse section  58  from groove  36 , and spring  55  then forces the blood collection unit  50  to pivot downwards, about pivot pins  53 ,  54 .  FIG. 6  provides a more detailed view of the blood collection member  50  in which the pivot pins  53 ,  54  can be seen. These are located in holders  35  extending from top shell  30 , one of which is visible in the detailed view of  FIG. 7 . 
     As a result of the pivoting movement, the lower edge  53  engages the test strip  80 , and blood flows by capillary action from groove  52  into the bibulous material of the test strip  80 . 
     The actuator  60  is further locked into the closed position. Latch  35  via recess  36  now engages the lower projection  64  of actuator  60 , so that it is retained in the closed position. The retention assists in producing positive pressure within the reservoir  100  and well  101 , so that the fluid is forced from reservoir  100  and into the test strip  80 , so as to minimise surface losses of the test fluid and provide reliable delivery to the test strip  80 . 
     The user then waits the appropriate time, and determines (in this case) if lines appear in the test and control windows. The test result can thereby be determined, together with verification that a valid test has been conducted. 
     It is generally preferable that the blood is always delivered at the same time, or earlier, than the test fluid, particularly if the fluid is a buffer. The purpose of the buffer is to provide enough fluid to sufficiently drive the movement of the blood along the strip. If the buffer is added before the blood, or runs ahead of the blood, the test may not function correctly. 
     In one respect, the test fluid is added at about area  81  on the test strip, and blood is delivered from blood collection unit  50 , because the action of spring  55 , at about area  82 . Hence, even if the blood and buffer are added at the same time, the buffer is behind the blood. 
       FIGS. 8 and 9  illustrate the operation of the interlock member  90  in more detail.  FIG. 8  corresponds to the situation in  FIG. 3A , in which device  10  is ready for use, but the lancet  42  has not been prepared or fired. Lock post  91  is at it&#39;s original, left-most position, that is, closest to the lancet end. It will be understood that another lock post is located on the other side of the lower shell, as can be seen in  FIG. 2 . In this position, lock post  91  engages actuator post  66 , so that actuator  60  cannot be depressed. 
       FIG. 9  illustrate the situation in  FIG. 3C , after the lancet has been fired. Lock post  91  has now moved to the right, that is, to its position at the end closest to the actuator  60 . The lock posts  91  no longer engage the actuator posts  66  and actuator  60  can be depressed. 
     The arrangement illustrated has the actuator at the opposite end to the lancet. When the device is used for self test, this is convenient for the user, as they lance their finger at one end, place the blood onto the blood recess  51 , and operate the actuator from the other end. The interior structure is better organised that in arrangements in which the actuator, reservoir and lancet were all at the same end. 
     A further advantageous feature is that the actuator brings the blood into contact with the test strip in a controlled way, in which the movement is controlled by the device and is not dependant upon the force used by the user. The actuator simply releases the blood collection unit, no understanding or other control is required by the user. 
     Similarly, the more or less simultaneous release of test fluid and blood, preferably each onto their respective contact areas on the strip, means that the user need not worry about sequencing or volume control, or even timing—the device performs these tasks from a single actuator operation. 
     The reservoir unit is preferable formed and constructed as disclosed in more detail in PCT/AU2016/051134. While this is a suitable implementation, the present invention is not limited to a fluid delivery mechanism constructed in this manner. 
       FIGS. 10 and 11  illustrate respectively a full and a discharged fluid unit  105 . The unit includes a reservoir  100 , a well  101  with a discharge opening  102 , and a conduit  104  connecting reservoir  100  to well  101 . Conduit  104  is sealed by a frangible seal, which ruptures operatively under pressure from the actuator  60 . The reservoir is forced to close and forces fluid into well  101  and then through opening  102 , which is in contact with the test strip  80 . 
     The fluid unit  105  may be conveniently formed from laminated heat sealable material, with a relatively stronger seal around the periphery and overlapping edges  106 , with the weaker, frangible seal  103 , preferably formed as per the above referenced application. 
     The size of the fluid unit, as well as the capacity of the blood collecting unit, may be varied by appropriate dimensioning to suit the requirements of the test. It will be apparent that within the size constraints of the device, a variety of size options can be accommodated, so that the same basic device may be varied in those component only to provide volumes suitable for different tests. 
     The present invention may be implemented including electronic components, for example an automated reader for a lateral flow test, or an electronic test material. In such an implementation, the actuator may additionally serve to activate the electronics, for example using a projection to operate a switch to close a circuit.