Patent Description:
The presently disclosed and/or claimed inventive concept(s) relate to a device(s), kit(s), and method(s) for separating and metering a plasma sample for use in analyte(s) detection assays. More specifically, the presently disclosed and/or claimed inventive concept(s) relate to an improved device for separating, metering, and/or delivering a plasma sample obtained from a patient's whole blood sample for use in analyte(s) detection assays, as well as methods of use related thereto.

Numerous devices, kits, and methods exist for injecting liquid test samples within a reaction vessel for conducting assays that detect analytes that may be present in the liquid test samples. Such devices have been proven to be effective in diagnostic assays that detect the presence and quantity of certain analytes indicative of a patient's health.

<CIT> discloses a blood/plasma separator device. It comprises a plurality of foldable quadrants divided by parallel crease lines in a bifacial sheet, an aperture in the bifacial sheet used to collect a biological sample, and an analytic membrane array. The analytic array includes a separation membrane and a capture membrane, which may be stacked together at overlapping regions. The liquid component of a biological sample flows from the separator membrane to the capture membrane which is configured to trap solid components and to filter a plasma fraction of a whole blood specimen. In an embodiment, the analytic membrane is positioned over a plasma collection chamber or vessel. <CIT> teaches a membrane array comprising three porous membranes which are overlapping in a stair-step configuration. The first and second membrane are separation membranes, wherein the second separation membrane has a smaller pore size than the first separation membrane. The first membrane contains a detection reagent such as a labeled antibody, whereas the third membrane is an analytical membrane which contains a capture reagent and has a pore size even smaller than that of the second membrane. It can bind a large amount of capture reagent, e.g. an antibody or an antigen, which reacts with the analyte/detection reagent complex. The earlier but not pre-published <CIT> discloses a device for collecting plasma from a blood sample. The plasma is collected in an absorbent membrane inside the device. After removing the membrane from the device, the plasma can be eluted from the plasma for further testing.

Hemolysis, as used herein, refers to the destruction, dissolution, or rupturing of red blood cells (RBCs) which results in the release of hemoglobin into the surrounding fluid(s). When a patient's liquid test sample is a whole blood sample, the hemoglobin is released into the surrounding plasma. The occurrence of a particular analyte(s) present in a patient's plasma sample may be indicative of a patient's medical condition or the mishandling of a sample, for instance, by a laboratory technician.

The separation of plasma has historically been accomplished through the centrifugation of a patient's whole blood sample which generates plasma which then may be interrogated (either optically or electrochemically) for the detection of hemolyzed hemoglobin. While accurate, this process is time consuming, requires additional instrumentation, and is inefficient for point-of-care (POC) applications. Accordingly, there is a current need for an integrated, improved plasma separation and sample metering device that is able to separate and meter a patient's extracted plasma sample for use in at least one analyte(s) detection and/or diagnostic assay. It is to such devices, and methods that the presently disclosed and/or claimed inventive concept(s) is directed.

The foregoing object has been achieved with a sample device as claimed in claim <NUM> and a method of separating and metering a plasma sample from a patient's liquid test sample for use within at least one diagnostic assay, as claimed in claim <NUM>.

Before explaining at least one embodiment of the inventive concept(s) in detail by way of exemplary drawings, experimentation, results, and laboratory procedures, it is to be understood that the inventive concept(s) is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings, experimentation and/or results. The inventive concept(s) is capable of other embodiments or of being practiced or carried out in various ways. As such, the language used herein is intended to be given the broadest possible scope and meaning; and the embodiments are meant to be exemplary-not exhaustive.

Unless otherwise defined herein, scientific and technical terms used in connection with the presently disclosed and/or claimed inventive concept(s) shall have the meanings that are commonly understood by those of ordinary skill in the art. The foregoing techniques and procedures are generally performed according to conventional methods well known in the art and as described in various general and more specific references that are cited and discussed throughout the present specification. The nomenclatures utilized in connection with, and the laboratory procedures and techniques of, analytical chemistry, synthetic organic chemistry, and medicinal and pharmaceutical chemistry described herein are those well-known and commonly used in the art.

All patents, published patent applications, and non-patent publications mentioned in the specification are indicative of the level of skill of those skilled in the art to which this presently disclosed and/or claimed inventive concept(s) pertains.

As utilized in accordance with the present disclosure, the following terms, unless otherwise indicated, shall be understood to have the following meanings:.

The use of the word "a" or "an" when used in conjunction with the term "comprising" in the claims and/or the specification may mean "one," but it is also consistent with the meaning of "one or more," "at least one," and "one or more than one. " The singular forms "a," "an," and "the" include plural referents unless the context clearly indicates otherwise. Thus, for example, reference to "a compound" may refer to <NUM> or more, <NUM> or more, <NUM> or more, <NUM> or more or greater numbers of compounds. The term "plurality" refers to "two or more. " The use of the term "or" in the claims is used to mean "and/or" unless explicitly indicated to refer to alternatives only or the alternatives are mutually exclusive, although the disclosure supports a definition that refers to only alternatives and "and/or. " Throughout this application, the term "about" is used to indicate that a value includes the inherent variation of error for the device, the method being employed to determine the value, or the variation that exists among the study subjects. For example but not by way of limitation, when the term "about" is utilized, the designated value may vary by ± <NUM>% or ± <NUM>%, or ± <NUM>%, or ± <NUM>%, or ± <NUM>% from the specified value, as such variations are appropriate to perform the disclosed methods and as understood by persons having ordinary skill in the art. The use of the term "at least one" will be understood to include one as well as any quantity more than one, including but not limited to, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, etc. The term "at least one" may extend up to <NUM> or <NUM> or more, depending on the term to which it is attached; in addition, the quantities of <NUM>/<NUM> are not to be considered limiting, as higher limits may also produce satisfactory results. In addition, the use of the term "at least one of X, Y and Z" will be understood to include X alone, Y alone, and Z alone, as well as any combination of X, Y and Z. The use of ordinal number terminology (i.e., "first", "second", "third", "fourth", etc.) is solely for the purpose of differentiating between two or more items and is not meant to imply any sequence or order or importance to one item over another or any order of addition, for example.

As used in this specification and claim(s), the terms "comprising" (and any form of comprising, such as "comprise" and "comprises"), "having" (and any form of having, such as "have" and "has"), "including" (and any form of including, such as "includes" and "include") or "containing" (and any form of containing, such as "contains" and "contain") are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

As used herein, the term "substantially" means that the subsequently described event or circumstance completely occurs or that the subsequently described event or circumstance occurs to a great extent or degree. For example, the term "substantially" means that the subsequently described event or circumstance occurs at least <NUM>% of the time, or at least <NUM>% of the time, or at least <NUM>% of the time.

As used herein, the phrase "associated with" includes both direct association of two moieties to one another as well as indirect association of two moieties to one another. Non-limiting examples of associations include covalent binding of one moiety to another moiety either by a direct bond or through a spacer group, non-covalent binding of one moiety to another moiety either directly or by means of specific binding pair members bound to the moieties, incorporation of one moiety into another moiety such as by dissolving one moiety in another moiety or by synthesis, and coating one moiety on another moiety.

The term "liquid test sample" as used herein will be understood to include any type of biological fluid sample that may be utilized in accordance with the presently disclosed and/or claimed inventive concept(s). Examples of biological samples that may be utilized include, but are not limited to, whole blood or any portion thereof (i.e., plasma or serum), saliva, sputum, cerebrospinal fluid (CSF), intestinal fluid, intraperitoneal fluid, cystic fluid, sweat, interstitial fluid, tears, mucus, urine, bladder wash, semen, combinations, and the like. The volume of the sample utilized in accordance with the presently disclosed and/or claimed inventive concept(s) is from about <NUM> to about <NUM> microliters. As used herein, the term "volume" as it relates to the liquid test sample utilized in accordance with the presently disclosed and/or claimed inventive concept(s) means from about <NUM> microliter to about <NUM> microliters, or from about <NUM> microliter to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or less than or equal to about <NUM> microliters, or less than or equal to about <NUM> microliters. In one non-limiting embodiment of the presently disclosed and/or claimed inventive concept(s), the liquid test sample is a patient's whole blood sample comprising and/or consisting of about <NUM> microliters to about <NUM> microliters in volume.

The term "patient" includes human and veterinary subjects. In certain embodiments, a patient is a mammal. In certain other embodiments, the patient is a human. "Mammal" for purposes of treatment refers to any animal classified as a mammal, including human, domestic and farm animals, nonhuman primates, and zoo, sports, or pet animals, such as dogs, horses, cats, cows, etc..

The term "plasma" refers to the liquid component of blood that is responsible for holding the blood cells in a whole blood sample in suspension that carries cells and proteins throughout the body. In one non-limiting embodiment, plasma may comprise and/or consist of dissolved proteins and/or analyte(s), such as, by way of example only, serum albumins, globulins, and fibrinogen, glucose, clotting factors, electrolytes, such as, by way of example only, sodium, calcium, magnesium, bicarbonate, chloride ions, hormones, carbon dioxide, and oxygen.

The term "reaction vessel" includes any device(s) capable of performing at least one diagnostic assay as described herein. The reaction vessel may perform the diagnostic assay(s) manually, but, in most instances, the reaction vessel will be inserted into a system that automates the performance of the diagnostic assay(s). In one non-limiting embodiment, the reaction vessel comprises a reaction cassette for use in automated diagnostic assays conducted by the DCA Vantage® Analyzer commercially available from Siemens Healthineers, Inc.

Turning now to particular embodiments, the presently disclosed and/or claimed inventive concept(s) relate to a device(s), and method(s) for separating and metering a plasma sample from a patient's liquid test sample for the performance of one or more diagnostic assays.

It is contemplated that virtually any reagent used in the fields of biological, chemical, or biochemical analyses and assays could be used in the devices, and methods of the presently claimed and disclosed inventive concept(s). It is contemplated that these reagents may undergo physical and/or chemical changes when bound to an analyte of interest whereby the intensity, nature, frequency, or type of signal generated by the reagent-analyte complex is directly proportional or inversely proportional to the concentration of the analyte existing within the fluid sample. These reagents may contain indicator dyes, metal, enzymes, polymers, antibodies, and electrochemically reactive ingredients and/or chemicals that, when reacting with an analyte(s) of interest, may exhibit change in color.

Any method of detecting and measuring the analyte in a fluid sample can be used in the devices, and methods of the presently claimed and inventive concepts. A variety of assays for detecting analytes are well known in the art and include, but are not limited to, chemical assays, enzyme inhibition assays, antibody stains, latex agglutination, latex agglutination inhibition and immunoassays, such as, radioimmunoassays. The term "antibody" herein is used in the broadest sense and refers to, for example, intact monoclonal antibodies, polyclonal antibodies, multi-specific antibodies (e.g., bispecific antibodies), and to antibody fragments that exhibit the desired biological activity (e.g., antigen/analyte-binding). The antibody can be of any type or class (e.g., IgG, IgE, IgM, IgD, and IgA) or sub-class (e.g., IgG1, IgG2, IgG3, IgG4, IgA1, and IgA2).

While immunoassays (including, but not limited to, sequential analytical chemical and immunoassays) are primarily discussed herein for the detection of at least one analyte of interest present in a liquid test sample, a person having ordinary skill in the art should readily understand that the presently disclosed and/or claimed inventive concept(s) are not strictly limited to immunoassays and may include, by way of example and not by limitation, chemical and chemical-based assays, nucleic acid assays, lipid-based assays, and serology-based assays. Immunoassays, including radioimmunoassays and enzyme-linked immunoassays, are useful methods for use with the presently claimed and disclosed inventive concepts. A variety of immunoassay formats, including, for example, competitive and non-competitive immunoassay formats, antigen/analyte capture assays and twoantibody sandwich assays can be used in the methods of the invention. Enzyme-linked immunosorbent assays (ELISAs) can be used in the presently claimed and disclosed inventive concepts, as well. In the case of an enzyme immunoassay, an enzyme is typically conjugated to a second antibody, generally by means of glutaraldehyde, periodate, hetero-bifunctional crosslinking agents, or biotin-streptavidin complexes. As will be readily recognized, however, a wide variety of different conjugation techniques exist which are readily available for use with the presently disclosed and/or claimed inventive concept(s) to one skilled in the art.

Assays, including, but not limited to, immunoassays, nucleic acid capture assays, lipid-based assays, and serology-based assays, can be developed for a multiplexed panel of proteins, peptides, and nucleic acids which may be contained within a liquid test sample, with such proteins and peptides including, for example but not by way of limitation, albumin, microalbumin, cholesterol, triglycerides, high-density lipoproteins, low-density lipoproteins, hemoglobin, myoglobin, α-<NUM>-microglobin, immunoglobins, enzymes, proteins, glycoproteins, protease inhibitors, drugs, cytokines, creatinine, and glucose. The device(s), and method(s) disclosed and/or claimed herein may be used for the analysis of any liquid test sample, including, without limitation, whole blood, plasma, serum, or urine.

Referring now to the Figures, and more particularly to <FIG>, shown therein is a non-limiting embodiment of an improved sample device <NUM> that is configured in a collection position for the collection of a patient's liquid test sample <NUM>. In one non-limiting embodiment, the sample device <NUM> comprises and/or consists of a top portion <NUM>, a bottom portion <NUM>, at least one red blood cell capture membrane <NUM>, and at least one plasma membrane <NUM>.

As shown in <FIG>, the top portion <NUM> comprises a first end <NUM>, a second end <NUM>, a top side <NUM>, a bottom side <NUM>, and a sample channel <NUM>. Suitable materials for constructing the top portion <NUM>, include, without limitation, synthetic and/or naturally-occurring or derived polymers (both organic and/or inorganic), such as, by way of example only, thermoplastic polymer(s), thermoset polymer(s), elastomer(s), and/or synthetic fiber(s) such as low-density polyethylene, high density polyethylene, polystyrene, polyvinylchloride, styrene butadiene, polyacrylics, polyvinyl acetate, and combinations thereof. The top portion <NUM> can be configured to be any shape capable of accomplishing the presently disclosed and/or claimed inventive concept(s), including, without limitation, circular, ovular, triangular, square, rectangular, trapezoidal, pentagonal, hexagonal, heptagonal, octagonal, nonagonal, decagonal, or polygonal.

The top portion <NUM> comprises a sample channel <NUM> that is adapted to collect a patient's liquid test sample <NUM>, the sample channel <NUM> further comprising a first end <NUM> having an opening for receiving the patient's liquid test sample <NUM> and a second end <NUM>, wherein at least a portion of the second end <NUM> is open to, in direct contact with, and/or in fluid communication with at least a portion of the red blood cell capture membrane <NUM> (discussed in greater detail hereinbelow). When the sample device <NUM> is in a collection position, the sample channel <NUM> collects the patient's liquid test sample <NUM> for instance, via capillary action, when the opening of the first end <NUM> of the sample channel <NUM> is in contact with the patient's liquid test sample <NUM>. However, a person having ordinary skill in the art should readily appreciate that the patient's liquid test sample <NUM> can be collected by the sample channel <NUM> via any method commonly known in the art, including, without limitation, via creation of a negative pressure differential that draws the patient's liquid test sample <NUM> into the sample channel <NUM>. The size and volume-capacity of the sample channel <NUM> will vary depending on the type and quantity of the patient's liquid test sample <NUM> being collected. In certain non-limiting embodiments, the sample channel <NUM> may be adapted and sized to hold volumes of from about <NUM> microliter to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or from about <NUM> microliter to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or from about <NUM> to about <NUM> microliters, or less than or equal to about <NUM> microliters. By way of example only, and not by way of limitation, the volume capacity of the sample channel <NUM> may comprise a volume of from about <NUM> microliters to about <NUM> microliters when the patient's liquid test sample <NUM> is whole blood. While shown in <FIG> as being formed within the top portion <NUM> of the sample device <NUM> (for instance, by way of example only, via injection molding), a person having ordinary skill in the art should readily appreciate that the sample channel <NUM> may be formed by the securement of the top portion <NUM> and the bottom portion <NUM> such that the sample channel <NUM> is defined by a portion of the bottom side <NUM> of the top portion <NUM> and a bottom side <NUM> of the bottom portion <NUM>.

The sample device <NUM> further comprises the bottom portion <NUM>, the bottom portion <NUM> comprising and/or consisting of a first end <NUM>, a second end <NUM>, a top side <NUM>, and a bottom side <NUM>. The bottom portion may be constructed from and shaped in any manner as previously described with respect to the top portion <NUM>. As previously discussed, the sample channel <NUM> may be formed from the securement of the top portion <NUM> and the bottom portion <NUM> to one another via, by way of example only, adhesive(s) commonly known in the art and/or via welding. When the sample channel <NUM> is formed in this manner, an opening is formed at the first end <NUM> of the sample channel <NUM>, wherein the opening is defined by the second end <NUM> of the top portion <NUM> and the second end <NUM> of the bottom portion <NUM>.

Regardless of the manner in which the sample channel <NUM> is formed, the sample channel <NUM> extends longitudinally from the second end <NUM> of the top portion <NUM> and the second end <NUM> of the bottom portion <NUM> such that the sample channel <NUM> is substantially parallel in orientation to the top side <NUM> of the top portion <NUM> and the top side <NUM> of the bottom portion <NUM>. In one non-limiting embodiment the distance from the first end <NUM> of the sample channel <NUM> to the second end <NUM> of the sample channel is about <NUM> centimeter, although a person having ordinary skill in the art should readily understand that the abovereferenced distance of the sample channel <NUM> may be any distance capable of accomplishing the presently disclosed and/or claimed inventive concept(s). In one non-limiting embodiment, when the sample channel <NUM> is formed from the securement of the top portion <NUM> and bottom portion <NUM> to one another, the top portion <NUM> and bottom portion <NUM> are configured such that the sample channel <NUM> is capable of drawing in a patient's liquid test sample <NUM> through the opening of the first end <NUM> of the sample channel <NUM> via capillary action when the sample device <NUM> is placed in the collection position.

In one non-limiting embodiment, at least a portion of one wall forming the inside of the sample channel <NUM> may be coated or partially coated with at least one anticoagulant compound(s), including, without limitation, sodium heparin, lithium heparin, warfarin, rivaroxaban, dabigatran, apixaban, edoxaban, enoxaparin, fondaparinux, ethylenediaminetetraacetic acid (EDTA), and combinations thereof.

The sample device <NUM> further comprises at least one red blood cell capture membrane <NUM>, the red blood cell capture membrane <NUM> comprising and/or consisting of a first end <NUM> and a second end <NUM>. As previously described, in one non-limiting embodiment, a portion of the red blood cell capture membrane <NUM> at or near the second end <NUM> of the red blood cell capture membrane <NUM> is in direct contact with and/or in fluid communication with at least the second end <NUM> of the sample channel <NUM> such that the patient's liquid test sample <NUM> may be drawn into the red blood cell capture membrane <NUM> via, for instance, capillary action from the second end <NUM> of the sample channel <NUM>. In addition, as shown in <FIG>, the red blood cell capture membrane is positioned and contained entirely between the top portion <NUM> and the bottom portion <NUM> of the sample device <NUM> and is configured in a substantially parallel orientation to the sample channel <NUM>; however, a person having ordinary skill in the art should readily appreciate that the red blood cell capture membrane <NUM> may be oriented in any position capable of accomplishing the presently disclosed and/or claimed inventive concept(s). The red blood cell capture membrane <NUM> may be constructed of any material capable of substantially separating and retaining red blood cells from a patient's liquid test sample (i.e., a whole blood sample), while allowing the plasma to freely move through the red blood cell capture membrane <NUM> into the plasma membrane <NUM> (described in further detail hereinbelow). Suitable construction materials for the red blood cell capture membrane <NUM> include, but are not limited to, lectins, such as, by way of example only, concanavalin A, lentil lectin, potato lectin, snowdrop lectin, ricin, peanut agglutinin, jacalin, hairy vetch lectin, wheat germ agglutinin, elderberry lectin, maackia amurensis hemoagglutinin, ulex europaeus agglutinin, and aleuria aurantia lectin, anti-human red blood cell antibodies, asymmetric polysulfone membrane(s), and combinations thereof. In one non-limiting embodiment, the red blood cell capture membrane <NUM> comprises and/or consists of a potato lectin bound cellulose membrane.

The red blood cell capture membrane <NUM> (and/or the plasma membrane <NUM>) may further comprise and/or consist of at least one dye to facilitate the visual detection of when the patient's liquid test sample <NUM> within the red blood cell capture membrane <NUM> and/or the plasma membrane <NUM>. Any dye(s) commonly known in the art may be used in accordance with the presently disclosed and/or claimed inventive concept(s).

The sample device <NUM> further comprises at least one plasma membrane <NUM>, the plasma membrane <NUM> comprising and/or consisting of a first end <NUM> and a second end <NUM>. In one non-limiting embodiment, and as shown in <FIG>, a portion of the plasma membrane <NUM> at or near the first end <NUM> of the plasma membrane <NUM> is in direct contact with at least the second end <NUM> of the red blood cell capture membrane <NUM> such that the patient's plasma sample (as the red blood cells within the patient's liquid test sample <NUM> are substantially retained within the red blood cell capture membrane <NUM>) is drawn into the plasma membrane <NUM> via, for instance, capillary action or via gravitational flow from the second end <NUM> of the red blood cell capture membrane <NUM>. As shown in <FIG>, a portion of the plasma membrane <NUM> is contained entirely between the top portion <NUM> and the bottom portion <NUM>, for instance, at least the first end <NUM> of the plasma membrane <NUM> that is contact with the second <NUM> of the red blood cell capture membrane <NUM> is wholly contained between the top portion <NUM> and the bottom portion <NUM> of the sample device <NUM>. However, a portion of the plasma membrane <NUM>, comprising the second end <NUM>, protrudes from and/or through the first end <NUM> of the top portion <NUM> such that the plasma membrane comprises an exposed portion that is not contained within or between the top portion <NUM> and the bottom portion <NUM>. The exposed portion may be any dimension capable of accomplishing the presently disclosed and/or claimed inventive concept(s), including, without limitation, delivery of a patient's plasma sample <NUM> into a reaction channel <NUM> of a reaction vessel <NUM> for the conductance of one or more analyte(s) detection and/or diagnostic assays. In one non-limiting embodiment, the exposed portion may have an exposed surface area of about <NUM> square millimeters that holds a plasma sample of about <NUM> microliter for use in the one or more analyte(s) detection and/or diagnostic assays. In one non-limiting embodiment, once the exposed portion contains a pre-determined amount of a patient's plasma sample <NUM>, the exposed portion of the plasma membrane <NUM> may be pinched, separated from, or cut off (either before or after the sample device <NUM> is placed in a reaction vessel <NUM>) in order to meter and ensure that the exposed portion contains and delivers a predetermined volume of a patient's plasma sample into a reaction channel <NUM> for the conductance of at least one analyte(s) detection and/or diagnostic assays. In one non-limiting embodiment, the predetermined volume of the patient's plasma sample may comprise and/or consist of a volume of from about <NUM> microliters to about <NUM> microliters, or from about <NUM> microliter to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters, or from about <NUM> microliters to about <NUM> microliters. In one non-limiting embodiment, the predetermined volume of the patient's plasma sample is about <NUM> microliter.

In one non-limiting embodiment, the plasma membrane <NUM> may comprise a length of from about <NUM> microns to about <NUM> microns.

The plasma membrane <NUM> may be constructed of any material(s) capable of accomplishing the presently disclosed and/or claimed inventive concept(s). Suitable materials for construction of the plasma membrane <NUM> include, but are not limited to, cellulose (with or without binder), nitrocellulose, carboxymethylcellulose, glass fiber, synthetic paper, and combinations thereof.

Referring now to <FIG>, following collection of the patient's liquid test sample (such as, by way of example, a patient's whole blood sample), the sample device <NUM> is then inverted into a sampling position for placement within a reaction vessel <NUM>.

When placed in the sampling position (either before or after being placed within a reaction vessel <NUM>), the patient's liquid test sample <NUM> contained within the sample channel <NUM> flows (for instance, via gravity and/or via capillary action) from at least a portion of the second end <NUM> of the sample channel <NUM> into the red blood cell capture membrane <NUM>. As the patient's liquid test sample <NUM> contacts and enters into the red blood cell capture membrane <NUM>, the patient's liquid test sample <NUM> flows through the red blood cell capture membrane <NUM>. Accordingly, substantially all of the red blood cells present in the patient's liquid test sample <NUM> are captured by and retained within the red blood cell capture membrane <NUM> such that the sample that enters the plasma membrane <NUM> (for instance, from the second end <NUM> of the red blood cell capture membrane <NUM>) primarily comprises and/or consists of plasma <NUM> (as shown in greater detail in <FIG>), as well as any hemolyzed hemoglobin which may be contained therein). Once the plasma <NUM> enters into the plasma membrane <NUM> (for instance, into the first end <NUM> of the plasma membrane <NUM>, the plasma <NUM> travels in and throughout the plasma membrane <NUM> such that any additional impurities and/or remaining whole red blood cells are removed from the plasma <NUM>. In addition, the plasma membrane <NUM>, both through its configuration and structure (for instance, controlling the flow of the plasma <NUM> via the pore size(s) of, by way of example, a nitrocellulose plasma membrane <NUM>), allow for the accurate metering of the plasma <NUM> such that a predetermined volume of plasma <NUM> is delivered to and resides within the exposed portion near the second end <NUM> of the plasma membrane <NUM>.

In one non-limiting embodiment, the exposed portion near the second end <NUM> of the plasma membrane comprises a surface area of about <NUM> square millimeters and the predetermined volume of plasma comprises about <NUM> microliter.

Referring now to <FIG>, shown therein is the sample device <NUM> described in <FIG> which has been inserted in and secured within a reaction vessel <NUM> to form a diagnostic assay kit <NUM>. The description of the sample device <NUM> with respect to <FIG> is deemed wholly applicable to the sample device <NUM> shown in <FIG> and, for purposes of brevity, shall not be reiterated herein.

Once secured within a reaction channel <NUM> of the reaction vessel <NUM>, the predetermined volume (such as, by way for example only, about <NUM> microliter) of plasma <NUM> resides in and is contained within the exposed portion near the second end <NUM> of the plasma membrane <NUM>. As previously described, the sample device <NUM> may be configured such that once the predetermined volume of plasma is delivered into the exposed portion, the exposed portion is pinched, closed off, and/or separated from the remainder of the plasma membrane <NUM> such that the predetermined volume of plasma <NUM> within the exposed portion remains accurate prior to and during the conductance of one or more analyte(s) detection and/or diagnostic assay(s) within the reaction channel <NUM> of the reaction vessel <NUM>. Such pinching, closing, and/or separation of the exposed portion may occur prior to or during the insertion of the sample device <NUM> into the reaction vessel <NUM>.

After securement within the reaction channel <NUM> of the reaction vessel <NUM>, the exposed portion of the plasma membrane containing the predetermined volume of plasma <NUM> is then removed from the exposed portion by exposure to at least one liquid buffer and/or at least one liquid reagent (not shown), wherein the plasma sample <NUM> is mixed with the at least one buffer and/or at least one liquid reagent for the conductance of at least analyte(s) detection and/or diagnostic assay within the reaction chamber <NUM> of the reaction vessel <NUM>. In addition, once mixed, the plasma <NUM> mixed with the buffer(s) and/or liquid reagent(s) may further associate and/or react with at least one solid reagent, for instance at least one solid reagent present on reagent pad <NUM>, for the conductance of one or more analyte(s) detection and/or diagnostic assay(s), such as, for instance, an assay(s) for the detection of the presence of hemolyzed and/or glycated hemoglobin present within the plasma sample <NUM>.

Referring now to <FIG>, shown therein a cross-sectional view of the of the sample device <NUM> of <FIG> viewed from cross-sectional line x which depicts the flow of the patient's liquid test sample through the various components of the sample device <NUM>.

Claim 1:
A sample device (<NUM>) for separating and metering a plasma sample from a patient's liquid test sample (<NUM>), the liquid test sample being a whole blood sample, for the performance of one or more diagnostic assay, comprising:
a top portion (<NUM>), the top portion comprising a first end (<NUM>), a second end (<NUM>), a top side (<NUM>), a bottom side (<NUM>), and a sample channel (<NUM>) disposed between the top side and bottom side and having a first opening (<NUM>) at the second end (<NUM>) for collecting a patient's liquid test sample (<NUM>), the sample channel extending longitudinally from the second end (<NUM>) to the first end (<NUM>) of the top portion (<NUM>), wherein the first end has a second opening (<NUM>);
a bottom portion (<NUM>), the bottom portion comprising a first end (<NUM>), a second end (<NUM>), a top side (<NUM>), and a bottom side (<NUM>), wherein the bottom portion is secured to the top portion (<NUM>);
at least one red blood cell capture membrane (<NUM>), the at least one red blood cell capture membrane comprising a first end (<NUM>) and a second end (<NUM>), ;
at least one plasma membrane (<NUM>) comprising a first end (<NUM>) and a second end (<NUM>), wherein the first end (<NUM>) of the plasma membrane (<NUM>) is in substantially direct contact with the second end (<NUM>) of the at least one red blood cell capture membrane (<NUM>) and at least a portion of the second opening (<NUM>) is open to, in direct contact with, and/or in fluid communication with at least a portion of the red blood cell capture membrane (<NUM>),
characterized in that the at least one red blood cell capture membrane (<NUM>) is entirely contained between the top portion (<NUM>) and bottom portion (<NUM>) of the sample device (<NUM>), whereas a portion of the plasma membrane (<NUM>) comprising the second end (<NUM>), protrudes from and/or through the first end (<NUM>) of the top portion (<NUM>) such that the plasma membrane comprises an exposed portion that is not contained within or between the top portion (<NUM>) and the bottom portion (<NUM>) of the sample device (<NUM>).