Separation device and method of separating red blood cells from whole blood

Abstract

The present disclosure provides a separation device including a housing defining an inlet opening and an outlet opening. The housing includes a top wall, a bottom wall, and a plurality of sidewalls which together define a fluid chamber. The fluid chamber receives a flow of whole blood which at least includes red blood cells and plasma. The separation device further includes a mesh disposed within the housing, divides the fluid chamber into an upper chamber and a lower chamber, coupled with the plurality of sidewalls, and is spaced apart from each of the top wall and the bottom wall. The mesh includes a plurality of through-openings which separates the red blood cells from the whole blood. The red blood cells settle within the lower chamber under an effect of gravity. The outlet opening is in fluid communication with the upper chamber to facilitate removal of the plasma.

Description

[0001]

[0002] SEPARATION DEVICE AND METHOD OF SEPARATING RED BLOOD CELLS FROM WHOLE BLOOD

[0003] Technical Field

[0004] The present disclosure generally relates to a separation device and a method of separating red blood cells from whole blood.

[0005] Background

[0006] Typically, in diagnostic or therapeutic medical applications, there is a need for identification and quantification of biomarkers in whole blood. The identification and quantification of biomarkers often requires removal of red blood cells from whole blood prior to analysis. In an example, a concentration of the red blood cells may vary in a range of 35% - 50%, of a total volume of the whole blood which is known as a hematocrit level.

[0007] The high concentration of the red blood cells may interfere with biomarker assays. Specifically, a level of interference varies across the physiological hematocrit level that may lead to variation in a reported concentration of the biomarker. In an optical detection assay, such as an enzyme-linked immunoassay (ELISA), interference may be caused by light scattering effects and absorbance of hemoglobin in a visible spectrum. Further, the red blood cells may also interfere with electrochemical detection assay methods, for example those commonly utilized in glucose test strips. Further, chemical species, for example oxygen present in the red blood cells, may interfere with oxidation-reduction reactions. Blood viscosity may further be affected by the concentration of the red blood cells in the whole blood. For example, the high concentration of the red blood cells may result in high viscosity of the whole blood that may lead to slow molecular diffusion, thereby resulting in additional variability in kinetic-based assays caused by changes in molecular diffusion rates.

[0008] Therefore, to reduce the level of interference caused by the concentration of the red blood cells, removal of the red blood cells is needed prior to analysis to increase an accuracy and precision of biomarker detection.

[0009] Summary

[0010] Generally, the present disclosure relates to a separation device and a method of separating red blood cells from whole blood.

[0011] In a first aspect, the present disclosure provides a separation device. The separation device includes a housing defining an inlet opening and an outlet opening. The housing includes a top wall, a bottom wall, and a plurality of sidewalls. The top wall, the bottom wall, and the plurality of sidewalls together define a fluid chamber. The fluid chamber is in fluid communication with each of the inlet opening and the outlet opening. The fluid chamber is adapted to receive a flow of whole blood via the inlet opening. The whole blood at least includes red blood cells and plasma. The separation device further includes a mesh disposed within the housing and adapted to divide the fluid chamber into an upper chamber and a lower chamber. The mesh is coupled with the plurality of sidewalls of the housing and is spaced apart from each of the top wall and the bottom wall. The mesh includes a plurality of through- openings. The upper chamber is adapted to receive the whole blood via the inlet opening. The plurality of through-openings in the mesh separate the red blood cells from the whole blood by allowing passage of the red blood cells from the upper chamber to the lower chamber. The red blood cells settle within the lower chamber under an effect of gravity. The outlet opening is in fluid communication with the upper chamber to facilitate removal of the plasma from the upper chamber.

[0012] In a second aspect, the present disclosure provides a method of separating red blood cells from whole blood. The method includes providing a separation device. The separation device includes a housing defining an inlet opening and an outlet opening. The housing includes a top wall, a bottom wall, and a plurality of sidewalls. The top wall, the bottom wall, and the plurality of sidewalls together define a fluid chamber. The fluid chamber is in fluid communication with each of the inlet opening and the outlet opening. The separation device further includes a mesh disposed within the housing and adapted to divide the fluid chamber into an upper chamber and a lower chamber. The mesh is coupled with the plurality of sidewalls of the housing and is spaced apart from each of the top wall and the bottom wall. The mesh includes a plurality of through-openings. The method further includes receiving, via the inlet opening in the housing, a flow of whole blood within the fluid chamber. The whole blood at least includes red blood cells and plasma. The method further includes separating, by the plurality of through-openings in the mesh, the red blood cells from the whole blood by allowing passage of the red blood cells present in the whole blood from the upper chamber to the lower chamber. The method further includes settling the red blood cells within the lower chamber under an effect of gravity. The method further includes removing, via the outlet opening in the housing, the plasma from the upper chamber.

[0013] The details of one or more examples of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims. Brief Description of the Drawings

[0014] Exemplary embodiments disclosed herein may be more completely understood in consideration of the following detailed description in connection with the following figures. The figures are not necessarily drawn to scale. Like numbers used in the figures refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number.

[0015] FIG. 1 is a schematic cross-sectional view of a separation device, according to an embodiment of the present disclosure;

[0016] FIG. 2 is a schematic top view of a mesh associated with the separation device of FIG. 1;

[0017] FIG. 3 is a schematic cross-sectional view of a portion of the separation device of FIG. 1;

[0018] FIG. 4A is a schematic cross-sectional view of the separation device of FIG. 1 illustrating red blood cells received within a fluid chamber of the separation device;

[0019] FIG. 4B is a schematic cross-sectional view of the separation device of FIG. 1 illustrating the red blood cells settled within a lower chamber of the separation device; and

[0020] FIG. 5 is a flowchart for a method of separating red blood cells from whole blood, according to an embodiment of the present disclosure.

[0021] Detailed Description

[0022] In the following description, reference is made to the accompanying figures that form a part thereof and in which various embodiments are shown by way of illustration. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense.

[0023] In the following disclosure, the following definitions are adopted.

[0024] As used herein, all numbers should be considered modified by the term “about”. As used herein, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably.

[0025] The term “about”, unless otherwise specifically defined, means to a high degree of approximation (e.g., within + / - 5% for quantifiable properties) but again without requiring absolute precision or a perfect match.

[0026] As used herein as a modifier to a property or attribute, the term “generally”, unless otherwise specifically defined, means that the property or attribute would be readily recognizable by a person of ordinary skill but without requiring absolute precision or a perfect match (e.g., within + / - 20 % for quantifiable properties).

[0027] The term “substantially”, unless otherwise specifically defined, means to a high degree of approximation (e.g., within + / - 10% for quantifiable properties) but again without requiring absolute precision or a perfect match.

[0028] Terms such as same, equal, uniform, constant, strictly, and the like, are understood to be within the usual tolerances or measuring error applicable to the particular circumstance rather than requiring absolute precision or a perfect match.

[0029] As used herein, the terms “first” and “second” are used as identifiers. Therefore, such terms should not be construed as limiting of this disclosure. The terms “first” and “second” when used in conjunction with a feature or an element can be interchanged throughout the embodiments of this disclosure.

[0030] The term “coupled”, or “connected” may include direct physical connections between two or more components, or indirect physical connections between two or more components that are connected together by one or more additional components. For example, a first component may be coupled to a second component by being directly connected together or by being connected by a third component.

[0031] As used herein, the term “configured to” and like is at least as restrictive as the term “adapted to” and requires actual design intention to perform the specified function rather than mere physical capability of performing such a function.

[0032] As used herein, the terms “layer,” “sheet,” and “wall”, or variations thereof, are used to describe an article having a thickness that is small relative to its length and width.

[0033] Identification and quantification of biomarkers in whole blood often requires separation of red blood cells from whole blood prior to analysis. Typically, in centralized hospitals or clinical laboratories, separation of the red blood cells from whole blood is achieved via centrifugation that requires large volumes of whole blood collected intravenously in test tubes. During centrifugation, the red blood cells may be packed at a bottom of the tube resulting in plasma at a top of the tube which can be further accessed for analysis. In such centralized settings, biomarker detection in the separated plasma is typically performed on large, complex analyzers capable of automated liquid handling and access to frequent validation of assay performance via calibration.

[0034] Further, blood analyzers used outside a central lab also require removal of the red blood cells prior to analysis. However, intravenous quantities of blood and benchtop centrifugation may not be available or may be time consuming in situations where a rapid result is required. In some instances, finger pricks or glucose test strips may be used to collect whole blood for analysis. However, through finger pricks or glucose test strip, a very small quantity of whole blood for example, between 1 microliter and 5 microliters may be collected. Such quantity of whole blood may be subject to interferences caused by the red blood cells in the whole blood. Further, separation of the red blood cells from these small volumes of whole blood is difficult.

[0035] Therefore, there is a need for a simple and an efficient device that allows separation of the red blood cells from microliter quantities of whole blood without hemolysis, dilution, or significant loss of plasma to dead space.

[0036] The present disclosure relates to a separation device. The separation device includes a housing defining an inlet opening and an outlet opening. The housing includes a top wall, a bottom wall, and a plurality of sidewalls. The top wall, the bottom wall, and the plurality of sidewalls together define a fluid chamber. The fluid chamber is in fluid communication with each of the inlet opening and the outlet opening. The fluid chamber is adapted to receive a flow of whole blood via the inlet opening. The whole blood at least includes red blood cells and plasma. The separation device further includes a mesh disposed within the housing and adapted to divide the fluid chamber into an upper chamber and a lower chamber. The mesh is coupled with the plurality of sidewalls of the housing and is spaced apart from each of the top wall and the bottom wall. The mesh includes a plurality of through-openings. The upper chamber is adapted to receive the whole blood via the inlet opening. The plurality of through- openings in the mesh separate the red blood cells from the whole blood by allowing passage of the red blood cells from the upper chamber to the lower chamber. The red blood cells settle within the lower chamber under an effect of gravity. The outlet opening is in fluid communication with the upper chamber to facilitate removal of the plasma from the upper chamber.

[0037] The separation device may allow identification and quantification of biomarkers in whole blood by separating the red blood cells from the whole blood. The separation of the red blood cells may prevent interference with biomarker assays. Specifically, the separation device may reduce a level of interference caused by a concentration of the red blood cells by separating the red blood cells. The separation device may separate the red blood cells from the whole blood without any significant loss of plasma to dead space. Further, plasma with substantially less concentration of the red blood cells may be removed from the separation device that may further be used for analysis. Overall, the separation device may increase an accuracy and a precision of biomarker detection. Further, the separation device does not use centrifugation to remove the red blood cells from the whole blood that may otherwise require large volumes of whole blood. The separation device may allow separation of the red blood cells from small quantities of the whole blood without the need for dilution. Specifically, a viscosity of the whole blood or a concentration of the red blood cells in the whole blood may not have any effect on separation of the red blood cells, thereby eliminating the need for dilution of the whole blood sample that may otherwise change the concentration of the biomarker analyte in the plasma and may increase a lower detection limit of the biomarker assay. Further, the separation device may rapidly and efficiently separate the red blood cells from the whole blood.

[0038] Furthermore, the separation device may be simple in construction and does not require complex components for separating the red blood cells from the whole blood. The separation device may not require an external flow device to create flow patterns or turbulence inside the fluid chamber of the separation device for separating the red blood cells from the whole blood. The separation device may include a one-time use device. The separation device may prevent clogging of the mesh and thus, may eliminate a need of high pressure to elute the plasma that may lead to hemolysis and subsequent assay interference.

[0039] Moreover, the separation device may be combined with microstructure features, flocculant additives, and / or functionalized coatings to enhance separation of the red blood cells from the whole blood. Overall, the separation device may be time-efficient, cost-effective, easy to handle, and easy to manufacture.

[0040] FIG. 1 is a schematic cross-sectional view of a separation device 100. The separation device 100 includes a housing 102. The housing 102 may be made of a metallic material, a polymer, a ceramic material, and the like, without limiting the scope of the present disclosure. The housing 102 defines an inlet opening 106. The housing 102 also defines an outlet opening 108. The housing 102 includes a top wall 110. Each of the inlet opening 106 and the outlet opening 108 is defined in the top wall 110 of the housing 102. In the illustrated embodiment of FIG. 1, the inlet opening 106 and the outlet opening 108 are arranged at two opposite ends 140, 150 of the top wall 110.

[0041] In some embodiments, the top wall 110 may be made of a polymer. The top wall 110 may be made of polyolefin, polyester, polyamide, polyvinyl chloride, polyether ester, polyimide, polyester amide, polyacrylate, polyvinyl acetate, hydrolyzed derivatives of polyvinyl acetate, polyurethane, nylon, etc. The top wall 110 may be made from any polymer suitable for casting or extrusion. The polymer may provide flexibility and durability to the top wall 110. In some embodiments, the top wall 110 may be coated with a hydrophilic material. The hydrophilic material may prevent a fluid, for example, whole blood, to adhere to the top wall 110. In some embodiments, the top wall 110 may be modified, for example, by a surface treatment, application of surface coatings or agents, or incorporation of selected agents, such that the top wall 110 may be rendered hydrophilic to exhibit a contact angle of 90° or less with fluids. In some embodiments, surface treatments, such as, topical application of a surfactant, plasma treatment, vacuum deposition, polymerization of hydrophilic monomers, grafting hydrophilic moieties may be employed onto the top wall 110. In other embodiments, the top wall 110 may be treated via corona or flame treatment such that the top wall 110 may exhibit hydrophilic properties. In some embodiments, a surfactant or other suitable agent may be blended with a resin as an internal characteristic altering additive at the time of extrusion or casting to form the top wall 110.

[0042] The housing 102 further includes a bottom wall 112. In some embodiments, the bottom wall 112 may be made of a polymer. The bottom wall 112 may be made of polyolefin, polyester, polyamide, polyvinyl chloride, polyether ester, polyimide, polyester amide, polyacrylate, polyvinyl acetate, hydrolyzed derivatives of polyvinyl acetate, polyurethane, nylon, etc. The bottom wall 112 may be made from any polymer suitable for casting or extrusion. The polymer may provide flexibility and durability to the bottom wall 112.

[0043] In some embodiments, the bottom wall 112 may be coated with a hydrophilic material. The hydrophilic material may prevent a fluid, for example, whole blood to adhere to the bottom wall 112. In some embodiments, the bottom wall 112 may be modified, for example, by a surface treatment, application of surface coatings or agents, or incorporation of selected agents, such that the bottom wall 112 may be rendered hydrophilic to exhibit a contact angle of 90° or less with fluids. In some embodiments, a surface treatment, such as, a topical application of a surfactant, plasma treatment, vacuum deposition, polymerization of hydrophilic monomers, grafting hydrophilic moieties may be employed onto the bottom wall 112. In other embodiments, the bottom wall 112 may treated via a corona or flame treatment such that the bottom wall 112 may exhibit hydrophilic properties. In some embodiments, a surfactant or other suitable agent may be blended with a resin as an internal characteristic altering additive at the time of extrusion or casting to form the bottom wall 112.

[0044] The housing 102 further includes a plurality of sidewalls 114, 115. In some examples, the housing 102 may include four sidewalls 114, 115, such that the housing 102 is substantially rectangular or square in shape. The sidewall 114 is disposed at the end 140 of the top wall 110. The sidewall 115 is disposed at the end 150 of the top wall 110. The top wall 110, the bottom wall 112, and the plurality of sidewalls 114, 115 together define a fluid chamber 116. The fluid chamber 116 is in fluid communication with each of the inlet opening 106 and the outlet opening 108. The fluid chamber 116 is adapted to receive a flow of the whole blood via the inlet opening 106. The whole blood at least includes red blood cells 126 and plasma. In some embodiments, the whole blood may include the red blood cells 126, white blood cells, platelets, and the plasma. In some embodiments, the red blood cells 126 may be present in high concentrations in the whole blood. Specifically, the concentration percentage of the red blood cells 126 in the whole blood may vary between 25% - 60%.

[0045] The separation device 100 further includes a mesh 120. The mesh 120 is disposed within the housing 102. The mesh 120 is adapted to divide the fluid chamber 116 into an upper chamber 122 and a lower chamber 124. The outlet opening 108 is in fluid communication with the upper chamber 122. Further, the outlet opening 108 is in fluid communication with the upper chamber 122 to facilitate removal of the plasma from the upper chamber 122. The upper chamber 122 has a first height Hl . In some embodiments, the height Hl may be in a range of 100 microns to 300 microns, without any limitations. The lower chamber 124 has a height H2 that is different from the first height Hl. In some embodiments, the height H2 may be equal to the second height H2. In some embodiments, the second height H2 may be in a range of 100 microns to 300 microns, without any limitations.

[0046] The mesh 120 is coupled with the plurality of sidewalls 114, 115 of the housing 102 and is spaced apart from each of the top wall 110 and the bottom wall 112.

[0047] FIG. 2 is a schematic top view of the mesh 120. FIG. 3 is a schematic cross-sectional view of a portion of the separation device 100 of FIG. 1. With reference to FIGS. 2 and 3, the mesh 120 includes a plurality of through-openings 130. The plurality of through-openings 130 have a size in a range of 25 microns to 300 microns, without any limitations. The plurality of through-openings 130 may allow the red blood cells 126 to pass from the upper chamber 122 towards the lower chamber 124. In some embodiments, the plurality of through-openings 130 may have a tapering profile. The tapering profile may prevent return of the red blood cells 126 from the lower chamber 124 towards the upper chamber 122.

[0048] The mesh 120 defines a thickness Ml . In some embodiments, the thickness Ml of the mesh 120 is in a range of 100 microns to 300 microns, without any limitations. The thickness Ml of the mesh 120 may be decided so as to provide efficient passage of the red blood cells 126 from the upper chamber 122 towards the lower chamber 124. The thickness Ml may be decided so as to prevent return of the red blood cells 126 from the lower chamber 124 towards the upper chamber 122. The mesh 120 is made of a plurality of fibers 134 that are knitted together. The plurality of fibers 134 may provide rigidity and durability to the mesh 120. Each of the plurality of fibers 134 defines an upper surface 136 that is shaped to allow passage of the red blood cells 126 from the upper chamber 122 to the lower chamber 124. The upper surface 136 of the each of the plurality of fibers 134 has a curved shape. The curved shape of the upper surface 136 of the each of the plurality of fibers 134 may allow the red blood cells 126 to pass from the upper chamber 122 towards the lower chamber 124 via the mesh 120. However, the upper surface 136 may have any other shape that allows passage of the red blood cells 126 towards the lower chamber 124, without limiting the scope of the present disclosure.

[0049] In some embodiments, the mesh 120 may be made of a polymer. The mesh 120 may be made of polyolefins, polyesters, polyamides, polyvinyl chloride, polyether esters, polyimides, polyester amide, polyacrylates, polyvinyl acetate, hydrolyzed derivatives of polyvinyl acetate, polyurethane, nylon, etc. In some embodiments, the mesh 120 may be made from any polymer suitable for casting or extrusion. The polymer material may provide flexibility and durability to the mesh 120.

[0050] In some embodiments, the mesh 120 may be coated with a hydrophilic material. The hydrophilic material may prevent a fluid, for example, the whole blood to adhere to the mesh 120. In some embodiments, the mesh 120 may be modified, for example, by a surface treatment, application of surface coatings or agents, or incorporation of selected agents, such that the mesh 120 may be rendered hydrophilic to exhibit a contact angle of 90° or less with fluids. In some embodiments, a surface treatment, such as, topical application of a surfactant, plasma treatment, vacuum deposition, polymerization of hydrophilic monomers, grafting hydrophilic moieties may be employed onto the mesh 120. In other embodiments, the mesh 120 may be treated via a corona or flame treatment such that the mesh 120 may exhibit hydrophilic properties. In some embodiments, a surfactant or other suitable agent may be blended with a resin as an internal characteristic altering additive at the time of extrusion or casting to form the mesh 120.

[0051] Referring to FIGS. 4A and 4B, the upper chamber 122 receives the whole blood via the inlet opening 106. The plurality of through-openings 130 (see FIG. 2) in the mesh 120 separate the red blood cells 126 from the whole blood by allowing passage of the red blood cells 126 from the upper chamber 122 to the lower chamber 124. The red blood cells 126 settle within the lower chamber 124 under an effect of gravity. Further, a static condition is maintained within the fluid chamber 116 for a pre-defined time to allow settling of the red blood cells 126 within the lower chamber 124 under the effect of gravity. The settling of red blood cells 126 under the effect of gravity may reduce a need of any external force to separate the red blood cells 126 from the whole blood. In some embodiments, the pre-defined time may be greater than 10 minutes. In some embodiments, the pre-defined time may be greater than 15 minutes. In some embodiments, the pre-defined time may be less than or equal to 30 minutes. The mesh 120 may reduce a need for filters and may prevent clogging of the separation device 100.

[0052] In an example, when the separation device 100 receives the whole blood via the inlet opening 106, the red blood cells 126 present inside the whole blood pass through the mesh 120 via the plurality of through-openings 130. The static condition is maintained for the predefined time such that the red blood cells 126 settle within the lower chamber 124. Further, a pressure may be applied at the outlet opening 108 to facilitate removal of the plasma from the upper chamber 122, via the outlet opening 108. Further, the mesh 120 prevents a return flow of the red blood cells 126 from the lower chamber 124 to the upper chamber 122 based on the application of the pressure at the outlet opening 108.

[0053] The separation device 100 may allow identification and quantification of biomarkers in the whole blood by separating the red blood cells 126 from the whole blood. The separation of the red blood cells 126 may prevent interference with biomarker assays. Specifically, the separation device 100 may reduce a level of interference caused by a concentration of the red blood cells 126 by separating the red blood cells 126. The separation device 100 may separate the red blood cells 126 from the whole blood without any significant loss of plasma to dead space. Further, plasma is removed from the separation device 100 via the outlet opening 108, that may be used for analysis. Overall, the separation device 100 may increase an accuracy and a precision of biomarker detection.

[0054] Further, the separation device 100 does not use centrifugation to remove the red blood cells 126 from the whole blood that may otherwise require large volumes of whole blood. The separation device 100 may allow separation of the red blood cells 126 from small quantities of the whole blood without the need for dilution. Specifically, a viscosity of the whole blood or a concentration of the red blood cells 126 in the whole blood may not have any effect on separation of the red blood cells 126, thereby eliminating the need for dilution of the whole blood sample that may otherwise change the concentration of the biomarker analyte in the plasma and may increase a lower detection limit of the biomarker assay. Further, the separation device 100 may rapidly and efficiently separate the red blood cells 126 from the whole blood.

[0055] Furthermore, the separation device 100 may be simple in construction and does not require complex components for separating the red blood cells 126 from the whole blood. The separation device 100 may not require an external flow device to create flow patterns or turbulence inside the fluid chamber 116 of the separation device 100 for separating the red blood cells 126 from the whole blood. The separation device 100 may include a one-time use device. The separation device 100 may prevent clogging of the mesh 120 and thus, may eliminate a need of high pressure to elute the plasma that may lead to hemolysis and subsequent assay interference.

[0056] Moreover, the separation device 100 may be combined with microstructured features, flocculant additives, and / or functionalized coatings to enhance separation of the red blood cells 126 from the whole blood. Overall, the separation device 100 may be time -efficient, cost- effective, easy to handle, and easy to manufacture.

[0057] FIG. 5 is a flowchart for a method 500 of separating red blood cells 126 from whole blood. With reference to FIGS. 1 to 5, at step 502, the separation device 100 is provided.

[0058] At step 504, the inlet opening 106 in the housing 102 receives the flow of whole blood within the fluid chamber 116.

[0059] At step 506, the plurality of through-openings 130 in the mesh 120 separates the red blood cells 126 from the whole blood by allowing passage of the red blood cells 126 present in the whole blood from the upper chamber 122 to the lower chamber 124. Further, at the step 506, the upper surface 136 of each of the plurality of fibers 134 allows the passage of the red blood cells 126 from the upper chamber 122 to the lower chamber 124.

[0060] At step 508, the red blood cells 126 are settled within the lower chamber 124 under the effect of gravity. At the step 508, the static condition is maintained within the fluid chamber 116 for the pre-defined time to allow settling of the red blood cells 126 within the lower chamber 124 under the effect of gravity.

[0061] At step 510, the plasma is removed from the upper chamber 122 via the outlet opening 108 in the housing 102. At the step 510, the pressure is applied at the outlet opening 108. At the step 510, the mesh 120 prevents the return flow of the red blood cells 126 from the lower chamber 124 to the upper chamber 122 based on the application of the pressure at the outlet opening 108.

[0062] TESTS

[0063] A test was performed to calculate a percentage change in a concentration of the red blood cells (RBC) through two different separation devices. The two different separation devices included the separation device 100 (shown in FIG. 1), and a separation device A (not shown). The separation device A was substantially similar to the separation device 100. However, a top wall, a mesh, and a bottom wall of the separation device A were made of polymer and were not coated with the hydrophilic material. Whereas the top wall 110, the mesh 120, and the bottom wall 112 of the separation device 100 were made of polymer and were coated with the hydrophilic material.

[0064] Each of the separation device 100 and the separation device A were placed on a horizontal surface. The inlet opening 106 of the separation device 100 and an inlet opening of the separation device A received microliter quantity of a blood sample. Each of the separation device 100 and the separation device A were maintained undisturbed for 15 minutes to allow the RBCs to settle through a corresponding mesh. A pressure was applied at outlet openings of each of the separation device 100 and the separation device A to collect the plasma above the mesh. The absorbance of the plasma collected from the outlet openings was measured according to a method described below.

[0065] A standard calibration curve was prepared from a dilution series of whole blood in water to correlate RBC count with absorbance at 406 nanometers (run). The blood sample tested was diluted in water and analyzed. Further, deionized water with a resistivity greater than 18 megaohm-centimeter (cm) was used to prepare a dilution. Absorbance at 406 nm was measured for each of the separation device 100 and the separation device A. The percentage of RBC reduction of the blood sample was calculated by comparing the absorbance of an aliquot i.e., a small portion of blood collected from each of the separation device 100 and the separation device A to the absorbance of the whole blood sample added to each of the separation device 100 and the separation device A according to equation 1 provided below:

[0066] [l-(Absorbance 406 nm output / Absorbance 406 nm input)] x 100 ..(Equation

[0067] 1) where, Absorbance 406 nm output is the absorbance of the 406 nm wavelength of the blood sample collected from each of the separation device 100 and the separation device A, and

[0068] Absorbance 406 nm input is the absorbance of the 406 nm wavelength of the blood sample added to the each of the separation device 100 and the separation device A.

[0069] The calculated values are summarized in Table 1 provided below.

[0070] Table 1

[0071] The data of Table 1 demonstrates that when each of the top wall 110, the bottom wall 112, and the mesh 120 of the separation device 100 were coated with the hydrophilic material, the percentage of RBC reduced in the whole blood was 37.9%. Further, when each of the top wall, the bottom wall, and the mesh of the separation device A were not coated with the hydrophilic material, the percentage of RBC reduced in the whole blood was 8%. The data demonstrates that when each of the top wall 110, the bottom wall 112, and the mesh 120 of the separation device 100 were made of polymer and were coated with the hydrophilic material, the percentage of RBC reduced in the whole blood increases. Since, the percentage of RBC reduced in the whole blood was greater in the separation device 100, as a result, the separation device 100 be effective in separation of the RBCs in the whole blood.

[0072] Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein.

[0073] As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” encompass embodiments having plural referents, unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and / or” unless the content clearly dictates otherwise.

[0074] Spatially related terms, including but not limited to, “proximate,” “distal,” “lower,” “upper,” “beneath,” “below,” “above,” and “on top,” if used herein, are utilized for ease of description to describe spatial relationships of an element(s) to another. Such spatially related terms encompass different orientations of the device in use or operation in addition to the particular orientations depicted in the figures and described herein. For example, if an object depicted in the figures is turned over or flipped over, portions previously described as below, or beneath other elements would then be above or on top of those other elements.

[0075] As used herein, when an element, component, or layer for example is described as forming a “coincident interface” with, or being “on,” “connected to,” “coupled with,” “stacked on” or “in contact with” another element, component, or layer, it can be directly on, directly connected to, directly coupled with, directly stacked on, in direct contact with, or intervening elements, components or layers may be on, connected, coupled or in contact with the particular element, component, or layer, for example. When an element, component, or layer for example is referred to as being “directly on,” “directly connected to,” “directly coupled with,” or “directly in contact with” another element, there are no intervening elements, components or layers for example.

[0076] Various examples have been described. These and other examples are within the scope of the following claims.

Claims

CLAIMS1. A separation device comprising: a housing defining an inlet opening and an outlet opening, wherein the housing includes a top wall, a bottom wall, and a plurality of sidewalls, wherein the top wall, the bottom wall, and the plurality of sidewalls together define a fluid chamber, wherein the fluid chamber is in fluid communication with each of the inlet opening and the outlet opening, wherein the fluid chamber is adapted to receive a flow of whole blood via the inlet opening, and wherein the whole blood at least includes red blood cells and plasma; and a mesh disposed within the housing and adapted to divide the fluid chamber into an upper chamber and a lower chamber, wherein the mesh is coupled with the plurality of sidewalls of the housing and is spaced apart from each of the top wall and the bottom wall, wherein the mesh includes a plurality of through-openings, wherein the upper chamber is adapted to receive the whole blood via the inlet opening, wherein the plurality of through-openings in the mesh separate the red blood cells from the whole blood by allowing passage of the red blood cells from the upper chamber to the lower chamber, wherein the red blood cells settle within the lower chamber under an effect of gravity, and wherein the outlet opening is in fluid communication with the upper chamber to facilitate removal of the plasma from the upper chamber.

2. The separation device of claim 1, wherein each of the plurality of through-openings have a size in a range of 25 microns to 300 microns.

3. The separation device of claim 1, wherein the mesh defines a thickness, and wherein the thickness of the mesh is in a range of 100 microns to 300 microns.

4. The separation device of claim 1, wherein the mesh is made of a polymer.

5. The separation device of claim 1, wherein the mesh is made of a plurality of fibers that are knitted together.

6. The separation device of claim 5, wherein each of the plurality of fibers defines an upper surface that is shaped to allow passage of the red blood cells from the upper chamber to the lower chamber.

7. The separation device of claim 6, wherein the upper surface of each of the plurality of fibers has a curved shape.

8. The separation device of claim 1, wherein the mesh is coated with a hydrophilic material.

9. The separation device of claim 1, wherein the top wall is made of a polymer.

10. The separation device of claim 1, wherein the top wall is coated with a hydrophilic material.

11. The separation device of claim 1, wherein the bottom wall is made of a polymer.

12. The separation device of claim 1, wherein the bottom wall is coated with a hydrophilic material.

13. The separation device of claim 1, wherein a static condition is maintained within the fluid chamber for a pre-defined time to allow settling of the red blood cells within the lower chamber under the effect of gravity.

14. The separation device of claim 13, wherein the pre-defined time is greater than 10 minutes.

15. The separation device of claim 1, wherein the upper chamber has a first height, and wherein the lower chamber has a second height that is different from the first height.

16. The separation device of claim 1, wherein each of the inlet opening and the outlet opening is defined in the top wall of the housing.

17. A method of separating red blood cells from whole blood, the method comprising: providing a separation device, wherein the separation device includes: a housing defining an inlet opening and an outlet opening, wherein the housing includes a top wall, a bottom wall, and a plurality of sidewalls, whereinthe top wall, the bottom wall, and the plurality of sidewalls together define a fluid chamber, and wherein the fluid chamber is in fluid communication with each of the inlet opening and the outlet opening; and a mesh disposed within the housing and adapted to divide the fluid chamber into an upper chamber and a lower chamber, wherein the mesh is coupled with the plurality of sidewalls of the housing and is spaced apart from each of the top wall and the bottom wall, and wherein the mesh includes a plurality of through-openings; receiving, via the inlet opening in the housing, a flow of whole blood within the fluid chamber, wherein the whole blood at least includes red blood cells and plasma; separating, by the plurality of through-openings in the mesh, the red blood cells from the whole blood by allowing passage of the red blood cells present in the whole blood from the upper chamber to the lower chamber; settling the red blood cells within the lower chamber under an effect of gravity; and removing, via the outlet opening in the housing, the plasma from the upper chamber.

18. The method of claim 17, wherein the step of settling the red blood cells within the lower chamber under the effect of gravity further includes maintaining a static condition within the fluid chamber for a pre-defined time to allow settling of the red blood cells within the lower chamber under the effect of gravity.

19. The method of claim 18, wherein the pre-defined time is greater than 10 minutes.

20. The method of claim 17, wherein the step of removing, via the outlet opening in the housing, the plasma from the upper chamber further includes applying a pressure at the outlet opening.

21. The method of claim 20, wherein the step of removing, via the outlet opening in the housing, the plasma from the upper chamber further includes preventing, by the mesh, a return flow of the red blood cells from the lower chamber to the upper chamber based on the application of the pressure at the outlet opening.

22. The method of claim 17, wherein each of the plurality of through-openings have a size in a range of 25 microns to 300 microns.

23. The method of claim 17, the mesh defines a thickness, and wherein the thickness of the mesh is in a range of 100 microns to 300 microns.

24. The method of claim 17, wherein the mesh is made of a polymer.

25. The method of claim 17, wherein the mesh is made of a plurality of fibers that are knitted together.

26. The method of claim 25, wherein each of the plurality of fibers defines an upper surface that is shaped to allow passage of the red blood cells from the upper chamber to the lower chamber, and wherein the step of separating, by the plurality of through-openings in the mesh, the red blood cells from the whole blood further includes allowing, by the upper surface of each of the plurality of fibers, the passage of the red blood cells from the upper chamber to the lower chamber.

27. The method of claim 26, wherein the upper surface of each of the plurality of fibers has a curved shape.

28. The method of claim 17, wherein the mesh is coated with a hydrophilic layer.

29. The method of claim 17, wherein the top wall is made of a polymer.

30. The method of claim 17, wherein the top wall is coated with a hydrophilic material.

31. The method of claim 17, wherein the bottom wall is made of a polymer.

32. The method of claim 17, wherein the bottom wall is coated with a hydrophilic material.

33. The method of claim 17, wherein the upper chamber has a first height, and wherein the lower chamber has a second height that is different from the first height.

34. The method of claim 17, wherein each of the inlet opening and the outlet opening is defined in the top wall of the housing.

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