Patent Description:
In-vitro diagnostic analyzers have been available for several decades. The market for these types of analyzers were typically for use in a central laboratory. The central laboratory was capable of testing for a wide variety of biomedical species typically in a patient's blood and/or blood plasma. Some of the tests were/are for key parameters associated with the treatment of diabetic patients.

Lately, there appears to be an on-going shift for such testing from central laboratory testing to point-of-care sites within a hospital. This shift provides for quicker test data results, which can be important in diagnosis and treatment of certain conditions. Point-of-care testing plays an important role in the management of critically ill patients and is widely used in the operating room, emergency room and intensive care units. These tests are no longer performed exclusively by skilled medical technologists but also by multiskilled personnel including nurses, respiratory therapists, emergency personnel, physicians, and other medical staff. To meet this demand, manufacturers have had to downsize the analyzers and simplify the test procedures so that only minimal training in performing the test procedures is required.

One key feature common to all point-of-care analyzers is that they must be either portable and/or transportable. Examples of such point-of-care analyzers include, but are not limited to, Opti CCA and Omni <NUM> critical care analyzers from Roche Diagnostics, a division of Hoffman-La Roche, Stat Profile Ultra C from Nova Biomedical Corporation, CRT from Nova Biomedical Corporation, and Dimension RxL from Dade Berhing, Inc. , a division of Siemens Healthcare Diagnostics.

More recently, there is a further shift occurring to testing in a physician's office or laboratory located within a physician's office. As testing moves away from the central laboratory, new single use medical devices have been developed to meet this need.

In the physician's office environment, there are numerous devices that utilize a capillary to collect finger stick samples for analysis. The capillary may be either glass or plastic. Typical analyses are for species such as HbA1c, lipids, etc..

Once the sample is collected, these capillary-based collection devices are loaded into an analytical cartridge, which is then loaded into an instrument for analysis. One example is described in document <CIT>. Further prior art is known from document <CIT> which discloses a pipette tip formed as one-piece from synthetic resinous material which has a flexible elongated extension at a distal end with an ultra thin wall thickness. Document <CIT> discloses another embodiment of a pipette tip which comprises a hinge which provides flexibility to a distal portion of the pipette tip.

Although the point-of-care and physician office analyzers are designed to be simple to use in nature, there are issues associated with them that can lead to erroneous results. The primary factor responsible for these erroneous results is the collection of the sample.

Capillary tubes, which may be made of glass or plastic, are typically used to collect a blood sample from a finger stick. The capillary tubes used to collect the blood/sample are volumetrically very precise. If a user fails to wipe the excess blood/sample from the outside surface of the capillary tube, erroneous results may be obtained due to an over-fill situation. In other words, the sample from the outside surface is combined with the sample in the capillary tube giving a test volume that is greater than needed for the particular analysis. On the other hand, if the user does wipe off the excess sample from the outside surface of the capillary tube and fails to exercise the proper care required when doing so, the user can draw sample out of the capillary tube. This situation also leads to erroneous results due to an under-fill situation. In other words, the sample remaining within the capillary is less that the amount of sample the point-of-care analyzer is expecting to receive for the analysis. The consequence is an erroneous result.

Further, currently available point-of-care analyzers require the use of blood plasma as the sample. This requires separation of the red blood cells from the plasma in a blood sample before obtaining test results. The present invention uses whole blood samples without the need to separate the red blood cells from the plasma before testing and obtaining meaningful test results.

It is an object of the present invention to provide a point-of-care analyzer that processes whole blood samples without the need to separate the blood cells from the blood plasma.

It is another object of the present invention to provide an apparatus and method that prevents erroneous results from a point-of-care analyzer caused by an under-fill or an over-fill situation.

It is a further object of the present invention to provide an apparatus and method where a minimally-trained healthcare worker can perform sample acquisition and sample testing in a point-of-care analyzer to obtain accurate results therefrom.

It is another object of the present invention to provide an apparatus and method to obtain accurate test results from a point-of-care analyzer without the need to use a trained instrument technologist for transferring a sample to be tested into the point-of-care analyzer.

It is another object of the present invention to provide disposable test cartridge for use in a point-of-care analyzer that prevents and/or reduces the possibility of an erroneous result obtained from the point-of-care analyzer.

The present invention achieves these and other objectives by providing a device and method with the features of the independent claims that ensures the correct amount of sample is presented to a disposable test cartridge for use in a point-of-care analyzer.

In one embodiment of the present invention, a disposable test cartridge for a point-of-care analyzer includes a cartridge body having a plurality of chambers where each of the plurality of chambers has an opening at a top of the cartridge body, a removable cartridge cover connected to the cartridge body and having a capillary-receiving aperture, a capillary wiper disposed within the capillary-receiving aperture where the capillary-receiving aperture is aligned with one of the plurality of chambers of the cartridge body, and a capillary element removably insertable into the cartridge cover where the capillary element has a capillary tube that extends into the capillary-receiving aperture and through the capillary wiper where a tip portion of the capillary tube extends into the cartridge body. Because the test cartridge is disposable, some of the plurality of testchambers contain a variety of items such as, for example, specific test reagents for specific test measurements, a disposable pipette, and the like. Further, in a marketable product, a sealing tape and/or foil is positioned over the top of the cartridge body in order to prevent contamination of the test chambers and reagents as well as for extending the storage life of the disposable test cartridge.

In the embodiment of the present invention, the capillary wiper has a tubular upper portion having an upper portion opening and a tapered lower portion having a lower portion aperture where the tubular upper portion and the tapered lower portion define an internal through space.

In the embodiment of the present invention, the capillary wiper has a lower portion aperture with a diameter smaller than an outside diameter of the capillary tube.

In still another embodiment of the present invention, the capillary wiper has an internal space within a lower portion that is also tapered.

In yet a further embodiment of the present invention, the capillary wiper is made of an elastomeric material.

In another embodiment of the present invention, the capillary element has a capillary element body with a top body opening in fluid communication with the capillary tube.

In one embodiment of the present invention, the cartridge cover has a wiper-receiving neck portion extending from the capillary-receiving aperture a predefined distance towards but spaced from the cartridge body.

In another embodiment, the tubular upper portion of the capillary wiper has a cylindrical recess with a diameter smaller than a diameter of the wiper-receiving neck portion of the cartridge cover.

In one embodiment of the present invention, the tubular upper portion of the capillary wiper has a lower tubular end that transitions to the tapered lower portion where the lower cylindrical end has a ledge portion that contacts the top of the cartridge body while the tapered lower portion extends into the one of the plurality of chambers of the cartridge body.

In one embodiment of the present invention, the tubular upper portion of the capillary wiper has an overall cylindrical outer shape and the tapered lower portion of the capillary wiper has a frustoconical outer shape.

In one embodiment of the present invention, the capillary wiper includes a tubular upper portion having a tubular top end, a tubular bottom end and an upper portion opening, a tapered lower portion having a base end and an apex end where the apex end has a lower portion aperture and where the base end is connected to the tubular bottom end of the tubular upper portion, and an open pathway between the upper portion opening and the lower portion aperture defining a volume for receiving a capillary tube therethrough. The upper portion opening has a larger cross-sectional area than the capillary tube and the lower portion aperture has a smaller cross-sectional area than the capillary tube.

In one embodiment, the tapered lower portion of the capillary wiper is made of an elastomeric material.

In another embodiment, the tubular upper portion and the tapered lowered portion are made of an elastomeric material.

In still another embodiment, the entire capillary wiper is made of an elastomeric material.

In one embodiment of the present invention, the tubular upper portion of the capillary wiper is adapted for attachment to a cartridge cover of the disposable test cartridge.

In one embodiment of the present invention, the capillary wiper is over-molded into a cartridge cover of the disposable test cartridge.

In another embodiment of the present invention, the open pathway within the tapered lower portion of the capillary wiper is tapered.

In one embodiment, a method to reduce erroneous results from a point-of-care analyzer caused by over-filling and under-filling of a sample disposed in a disposable test cartridge for use in the point-of-care blood analyzer is disclosed. The method includes the features of the independent method claim.

In another embodiment of the method of the present invention for reducing erroneous results from a point-of-care analyzer having a disposable test cartridge will now be described. The method includes obtaining a disposable test cartridge designed for the point-of-care analyzer. A finger prick sample is created by lancing a finger of a patient or a urine sample is obtained from the patient depending on the specific test cartridge used, which test cartridges are designed and configured with reagents for specific tests and sample types. For purposes of this explanation, the assumption will be that a blood sample from a finger prick is obtained and the disposable test cartridge specific for this type of sample and associated tests is used. For tests using a urine sample, the method is very similar except that a finger prick is not used. The capillary element is removed from the cartridge cover of the disposable test cartridge. The capillary tube of the capillary element is touched to the drop of blood sample to fill the capillary tube. The capillary element is returned to the disposable test cartridge from which it came. In other words, the capillary element is inserted through the capillary-receiving aperture in the extension portion top surface of the stepped extension portion of the cover extension of the disposable test cartridge and seated in the stepped extension portion. During the insertion and setting process, the capillary tube is inserted through the lower portion aperture located in the apex end of the capillary wiper. Because the cross-sectional area of the lower portion aperture is smaller than the cross-sectional area of the capillary tube, the lower portion aperture acts like a squeegee against the outside surface of the capillary tube and prevents any sample inadvertently disposed on the outside surface of the capillary tube from entering and being deposited into the chamber of test cartridge. The test cartridge is then inserted into the point-of-care analyzer for the automatic testing of the blood sample. Because the capillary wiper removes any sample from the outside surface of the capillary tube, erroneous results are prevented from an "over-filling" of the chamber in the test cartridge with sample. Likewise, since the capillary tube is not wiped by the user, there is no, or very little, chance that any sample within the capillary tube is removed inadvertently, which would lead to erroneous results from an "under-filling" of the chamber in the test cartridge with sample.

The preferred embodiments of the present invention are illustrated in <FIG>. <FIG> shows one embodiment of a disposable test cartridge <NUM> for use in a point-of-care analyzer <NUM>. Test cartridge <NUM> includes a cartridge body <NUM>, a cartridge cover <NUM>, a capillary element <NUM>, and a capillary wiper <NUM> (not shown). Capillary element <NUM> is removable from the cartridge cover <NUM>.

Turning now to <FIG>, there is illustrated a partial cross-sectional view of a portion of the disposable test cartridge <NUM> showing the capillary element <NUM> and the capillary wiper <NUM>. Capillary element <NUM> includes a capillary element body <NUM> having a top body surface <NUM>, a depending capillary element finger <NUM> defining a capillary element volume <NUM>, a top body opening <NUM> that communicates with capillary element volume <NUM>, and a capillary tube <NUM> extending from a finger end 66a. Capillary element volume <NUM> decreases in cross-sectional area from top body opening <NUM> to finger end 66a. It is understood that capillary element volume <NUM> is open and continuous from top body opening <NUM> and through capillary tube <NUM>. Capillary element volume <NUM> may have a continuous taper or a stepped taper or a plurality of concentric, reduced diameters. Capillary wiper <NUM> has an upper portion <NUM> and a tapered lower portion <NUM>. As can be seen, capillary tube <NUM> extends through tapered lower portion <NUM> of capillary wiper <NUM> and into one of a plurality of chambers <NUM> within cartridge body <NUM>.

<FIG> are exploded views of disposable test cartridge <NUM> shown in <FIG>. <FIG> is a front perspective view and <FIG> is a side cross-sectional view of test cartridge <NUM>. Cartridge body <NUM> has a plurality of chambers <NUM> extending below a cartridge body top surface <NUM>, each having an opening <NUM>. Each of the plurality of chambers <NUM> has a specific purpose such as receiving the test sample, holding a chemical reagent adapted for a specific test, one or more calibration standards, and the like. For example, disposable test cartridge <NUM> in combination with the point-of-care analyzer may provide test results that include, but are not limited to, HbA1C, eAG, total cholesterol, HDL cholesterol, triglycerides, LDL cholesterol, cholesterol/HDL ratio, non-HDL cholesterol, urine albumin, urine creatinine, and albumin/creatinine ratio. More specifically and referencing <FIG>, the plurality of chambers <NUM> of the cartridge body <NUM> are arranged in the following order. Chamber 22a contains a disposable pipette tip (not shown), chamber 22b is the sample receiving chamber into which capillary tube is inserted and the sample deposited, chamber 22c to 22f contain various reagents for determining a predefined set of test results, and chamber <NUM> is the mixing and measuring chamber for sample and reagents. Not shown in <FIG> is a foil seal that covers all of the openings <NUM> of the plurality of chambers <NUM> to prevent contamination of the chambers <NUM> and reagents therein.

Capillary wiper <NUM> has upper portion <NUM> and tapered lower portion <NUM>. Upper portion <NUM> and tapered lower portion <NUM> are tubular, meaning that capillary wiper <NUM> defines a capillary wiper volume <NUM>. A lower volume portion <NUM> is adapted to receive a portion of capillary finger element <NUM> and capillary tube <NUM>.

Cartridge cover <NUM> has a cover top surface <NUM> with a plurality of descending cover sides <NUM> forming a cover recess <NUM>. Extending upward from cover top surface <NUM> is cover extension <NUM> that also forms a recess portion 46a of cover recess <NUM>. Cover extension <NUM> has a stepped extension portion <NUM> with an extension portion top surface <NUM> and a capillary-receiving aperture <NUM> that communicates with portion 46a of cover recess <NUM>. A cover tube extension <NUM> extends a predefined distance from capillary-receiving aperture <NUM> into recess portion 46a. Cover tube extension <NUM> mates with upper portion <NUM> of capillary wiper <NUM>. Cover recess <NUM> receives a top portion <NUM> of cartridge body <NUM> and locked in place with releasable tabs 28a. Cartridge cover <NUM>, in this embodiment, also has a back side extension <NUM> with a back extension end 58a that is received within a cover receiving slot <NUM> located on cartridge body <NUM>. Back extension end 58a has a small sharp point 58b (more clearly shown in <FIG>) that is used by the point-of-care analyzer to pierce the foil covered openings <NUM> of the plurality of chambers <NUM> during use of the disposable test cartridge <NUM>. The pipette tip (not shown) is used by the analyzer to dilute the sample and select a predefined quantity of the diluted sample for mixing with the test reagents and subsequent measurement in chamber <NUM>. It is understood that the analyzer removes cartridge cover <NUM> and uses the back extension end 58a to pierce the foil seal once the capillary tube <NUM> and sample are inserted into and assembled with cartridge cover <NUM> and then the disposable test cartridge <NUM> is inserted into the analyzer <NUM>.

As previously discussed, capillary element <NUM> has element body <NUM>, top body surface <NUM>, depending capillary element finger <NUM> defining a capillary element volume <NUM>, top body opening <NUM> that communicates with capillary element volume <NUM>, and a capillary tube <NUM> extending from a finger end 66a. Capillary tube <NUM> has a tube distal end 72a that may optionally be tapered.

Turning now to <FIG>, there is illustrated various enlarged views of capillary wiper <NUM>. Capillary wiper <NUM> has two major portions, the upper portion <NUM> and a tapered lower portion <NUM>. Tapered lower portion <NUM> has a base end 88a and an apex end 88b where apex end 88b has lower portion aperture 88c. At the junction between upper portion <NUM> and tapered lower portion <NUM>, there are a plurality of optional upper portion protrusions 82b that extend in the same direction as tapered lower portion <NUM>. Upper portion protrusions <NUM> are spaced from each other in a radial array that provides a limited amount of compressibility. Upper portion protrusions <NUM> tend to stabilize cartridge wiper <NUM> when assembled between cartridge cover <NUM> and cartridge body <NUM>.

Capillary wiper volume <NUM> has lower volume portion <NUM> and an upper volume portion <NUM> in communication with lower volume portion <NUM>. Lower volume portion <NUM> is optionally tapered from its junction with upper volume portion <NUM> to lower portion aperture 88c. One advantage of having a tapered lower volume portion <NUM> is it provides a centering guide for capillary tube <NUM>. It is contemplated that an untapered cylindrical volume having a cross-sectional diameter greater than capillary tube <NUM> may also be used. In the embodiment illustrated, upper volume portion <NUM> is divided into two different cross-sectional areas, 98a and 98b, but could also have only one or more that two different cross-sectional areas depending on the structural configuration of cartridge cover <NUM>. In the embodiment illustrated, upper volume portion 98a has a larger cross-sectional diameter than upper volume portion 98b to better fit over cover tube extension <NUM> and provides a snug fit so that cover tube extension <NUM> retains capillary wiper <NUM> when cartridge cover <NUM> is removed during processing of the sample in disposable test cartridge <NUM> by point-of-care analyzer <NUM>.

<FIG> illustrates a distal end view of capillary wiper <NUM>. In this view, the radial positioning of optional upper portion protrusions 82b is clearly shown. Apex end 88b includes lower portion aperture 88c and tapered lower portion <NUM>. <FIG> illustrates a proximal end view of capillary wiper <NUM>. In this view, the concentric nature of capillary wiper volume <NUM> is shown. At the furthest point, there is shown lower portion aperture 88c and apex end 88b. Tapered lower portion <NUM> in this embodiment defines lower volume portion <NUM> as having a tapered shape which extends from upper volume portion <NUM> to apex end 88b. In this embodiment, upper volume portion <NUM> is divided into upper volume portion 98a and upper volume portion 98b.

Turning now to <FIG>, there is illustrated capillary tube <NUM> containing a sample <NUM> to be tested where the sample for testing is inside capillary tube <NUM> and sample <NUM> on the outside surface of capillary tube <NUM>. It is this sample <NUM> on the outside surface of capillary tube <NUM> that potentially leads to erroneous test results. Typically, a trained technologist would carefully wipe the outside of capillary tube <NUM> to remove the sample <NUM> on the outside surface of capillary tube <NUM>, being careful not to touch tube distal end 72a. If the sample <NUM> on the outside surface is not removed, the transfer of the sample <NUM> and <NUM> into the dilution chamber 22b would cause the sample to have a higher ratio of sample to diluent thus causing the test results to have higher values than they should have. If the distal end 72a is accidentally touched while wiping the outside surface of capillary tube <NUM>, an amount of sample within capillary tube <NUM> may be withdrawn leaving a smaller amount of sample available for dilution. This causes the sample to have lower values than they should have. Because point-of-care analyzer is designed to provide accurate measurements based on a specific predefined sample size, any over-filling of sample in the dilution chamber 22b caused by sample remaining on the outside surface of capillary tube <NUM> or any under-filling of sample in dilution chamber 22b caused by the inadvertent removal of a small amount of sample from the capillary tube <NUM> leads to erroneous results. This is even more of a problem for point-of-care analyzers since these types of analyzers are for use in a doctor's office, which do not employ highly trained technologists, who are used typically in central labs where hundreds of tests are run daily. These highly trained technologists have the techniques that ensure consistent results. The typical person in a doctor's office that would obtain the blood and/or urine sample for measurement by the point-of-care analyzer have other duties such as nurses, physician assistants, medical assistants, and the like that are not highly trained as lab technologists. The consequence is a higher number of inaccurate and erroneous results that could lead to improper diagnose and treatment of patients.

The use of capillary wiper <NUM> provides a marked improvement in results obtained from a point-of-care analyzer when operated by persons other than a trained instrument technologist. Two sets of test data were obtained using a point-of-care analyzer (Allegro by Nova Biomedical Corporation). The first set involved the use of a disposable test cartridge without the integral capillary wiper <NUM> and the second set involved the use of a test cartridge with the integral capillary wiper <NUM>. To simulate the effect of using a person that is not a trained instrument technologist, some of the capillary tubes <NUM> were intentionally over dosed with sample so that some sample was left on the outside surface of the capillary tube. This simulates the improper wiping and/or lack of wiping the outside surface of the capillary tube after obtaining a sample for testing. The tests consisted of ten (<NUM>) whole blood samples run with the integral capillary wiper <NUM> and ten (<NUM>) whole blood samples run without the integral capillary wiper. Measurements were made for total cholesterol (TC), triglycerides (TG), and high-density lipo-proteins (HDL). Standard deviation (STDEV), average value (AVG) and percent coefficient of variation (%CV) were determined for all sample points, for overdosed capillary tubes and for properly dosed capillary tubes for each set of test measurements.

Table <NUM> below contains the test data for the samples run using a disposable test cartridge with no capillary wiper. The letters "OD" under method represents a test sample with a capillary tube having sample on its outside surface (i.e. overdosed).

Table <NUM> is discloses the standard deviation, average values and percent coefficient of variation for the values in Table <NUM>.

<FIG> are schematic representations of the test data for each category (i.e. TC, TG and HDL) disclosed in Table <NUM>. Indicators were added to the drawings to bring attention to those values for the capillary tubes that had sample on the outside surface. As can be seen from the test data, each of the 'overdosed' capillaries (indicated by arrows in the <FIG>) reported higher values for total cholesterol, triglycerides and high-density lipo-proteins. Even the values for all tests (both standard dose and over-dosed samples) taken together reported higher values for total cholesterol, triglycerides and high-density lipo-proteins than for the properly-dosed capillaries only. The standard deviations, the average values and the percent coefficient of variation had significantly higher values for the capillary tubes with sample on the outside surface (i.e. overdosed capillaries) than the values for the capillary tubes that were properly dosed.

Table <NUM> below contains the test data for the samples run using a disposable test cartridge with a capillary wiper.

Table <NUM> discloses the standard deviation, average values and percent coefficient of variation for the values in Table <NUM>.

<FIG> are schematic representations of the test data for each category (i.e. TC, TG and HDL) disclosed in Table <NUM>. Indicators were added to the drawings to bring attention to those values for the capillary tubes that had sample on the outside surface. As can be seen from the test data, each of the 'overdosed' capillaries reported very similar values for total cholesterol, triglycerides and high-density lipo-proteins. Even the values for all tests (both standard dose and over-dosed samples) taken together reported similar values for total cholesterol, triglycerides and high-density lipo-proteins to those for the properly-dosed capillaries only. The standard deviations, the average values and the percent coefficient of variation had significantly similar values for the capillary tubes with sample on the outside surface (i.e. overdosed capillaries) to the values for the capillary tubes that were properly dosed.

The conclusion from this test data is that the use of a disposable test cartridge containing a capillary wiper provides consistently better and fewer erroneous results. Accordingly, even when a person that is not trained as an instrument technologist performs the acquisition and testing of a sample using a capillary tube for a point-of-care analyzer, the lack of wiping any excess sample from the capillary tube before inserting the capillary tube with sample into the disposable test cartridge still provides relatively accurate results as seen from the standard deviation, average value and percent coefficient of variation between the overdosed and properly dosed capillary tubes. Furthermore, not wiping the outside surface of capillary tube <NUM> prevents the inadvertent and accidental removal of sample from inside capillary tube <NUM>.

A method of reducing erroneous results from a point-of-care analyzer <NUM> having a disposable test cartridge <NUM> for receiving a test sample will now be discussed. The method includes providing a tubular, capillary wiper <NUM> having a pipette-shaped longitudinal cross-section with a tapered, elastomeric bottom portion <NUM> and a top opening <NUM> having a cross-sectional area greater than the cross-sectional area of a capillary tube <NUM> used with the disposable test cartridge <NUM> and a bottom opening 88c having a cross-sectional area smaller than the cross-sectional area of the capillary tube <NUM>. The method also includes disposing the capillary tube <NUM> into and through the capillary wiper <NUM> whereby the bottom opening 88c of the capillary wiper <NUM> expands around capillary tube <NUM> and removes excess sample from an outside surface of the capillary tube <NUM> as the capillary tube <NUM> is pushed through the bottom opening 88c and prevents the excess sample from being added to or with the sample within the capillary tube <NUM>.

For the illustrated disposable test cartridge <NUM>, the method will now be discussed. A disposable test cartridge <NUM> designed for the point-of-care analyzer <NUM> is obtained. A finger prick sample is created by lancing a finger of a patient or a urine sample is obtained from the patient depending on the specific test cartridge <NUM> used, which are designed and configured with reagents for specific tests and sample types. For purposes of this explanation, the assumption will be that a blood sample from a finger prick is obtained and the disposable test cartridge <NUM> specific for this type of sample and associated tests is used. For tests using a urine sample, the method is very similar except that a finger prick is not used. The capillary element <NUM> is removed from cartridge cover <NUM> of disposable test cartridge <NUM>. Capillary tube <NUM> of capillary element <NUM> is touched to the drop of blood sample to fill capillary tube <NUM>. Capillary element <NUM> is returned to disposable test cartridge from which it came. In other words, capillary element <NUM> is inserted through capillary-receiving aperture <NUM> in extension portion top surface <NUM> of stepped extension portion <NUM> of cover extension <NUM> of disposable test cartridge <NUM> and seated in stepped extension portion <NUM>. During the insertion and setting process, capillary tube <NUM> is inserted through lower portion aperture 88c located in apex end 88b of capillary wiper <NUM>. Because the cross-sectional area of lower portion aperture 88c is smaller than the cross-sectional area of capillary tube <NUM>, lower portion aperture 88c acts like a squeegee against the outside surface of capillary tube <NUM> and prevents any sample inadvertently disposed on the outside surface of capillary tube <NUM> from entering and being deposited into chamber 22b of test cartridge <NUM>. Cartridge <NUM> is then inserted into point-of-care analyzer <NUM> for the automatic testing of the sample. Because capillary wiper <NUM> removes any sample from the outside surface of capillary tube <NUM>, erroneous results are prevented from an "over-filling" of chamber 22b with sample. Likewise, since capillary tube <NUM> is not wiped by the user, there is no, or very little, chance that any sample within capillary tube <NUM> is removed inadvertently, which would lead to erroneous results from an "under-filling" of chamber 22b with sample.

Thus, the present invention provides a point-of-care analyzer with disposable test cartridge(s) that can be used by persons other than a highly trained instrument technologist and still obtain accurate results in a timely manner in a doctor office setting similar to the results obtained from tests performed by highly trained instrument technologists in central testing laboratories.

Claim 1:
A disposable test cartridge (<NUM>) for a point-of-care analyzer (<NUM>), the test cartridge (<NUM>) comprising:
a cartridge body (<NUM>) having a plurality of chambers (<NUM>) wherein each of the plurality of chambers (<NUM>) has an opening (<NUM>) at a top of the cartridge body (<NUM>);
a cartridge cover (<NUM>) connected to the cartridge body (<NUM>), the cartridge cover (<NUM>) having a capillary-receiving aperture (<NUM>) and a cover tube extension (<NUM>) extending from the capillary-receiving aperture (<NUM>) a predefined distance towards but spaced from the cartridge body (<NUM>);
an elastomeric tubular capillary wiper (<NUM>) disposed within and through the capillary-receiving aperture (<NUM>) defines a capillary wiper volume (<NUM>) wherein the tubular capillary wiper (<NUM>) and the capillary-receiving aperture (<NUM>) are aligned with one of the plurality of chambers (<NUM>) of the cartridge body (<NUM>), the tubular capillary wiper (<NUM>) having a tubular upper portion (<NUM>) with an upper portion opening (<NUM>) and a tapered lower portion (<NUM>) with a lower portion aperture (88c); and
a capillary element (<NUM>) removably insertable into the cartridge cover (<NUM>), the capillary element (<NUM>) having a capillary tube (<NUM>) that extends into the capillary-receiving aperture (<NUM>) and through the tubular capillary wiper (<NUM>) wherein a tip portion (72a) of the capillary tube (<NUM>) extends through the lower portion aperture (88c) and into the one of the plurality of chambers (<NUM>) of the cartridge body (<NUM>) wherein the lower portion aperture (88c) has a diameter smaller than an outside diameter of the capillary tube (<NUM>) and expands around the capillary tube (<NUM>).