WO2024150241A1 - A cartridge for analysis of a biological fluid - Google Patents

Abstract

The present disclosure discloses a cartridge (100) for analysis of a biological fluid. The cartridge (100) comprises a base plate (1) and an inlet (2). The base plate (1) is defined with a flow surface comprising a first passage (3) and a second passage (5) extending from the first passage (3). The first passage (3) is connected to a first analysis chamber (4) and the second 0 passage (5) is connected to a reagent chamber (7) comprising a plurality of reagents. The reagent chamber (7) is connected to a second analysis chamber (6) through a serpentine passage (8). The flow surface comprises a third analysis chamber (9) connected between the serpentine passage (8) and the second analysis chamber (6). The cartridge (100) allows a single step analysis of the biological fluid requiring minimal number of samples of the biological fluid from a subject.

Description

A CARTRIDGE FOR ANALYSIS OF A BIOLOGICAL FLUID

TECHNICAL FIELD

Present disclosure, in general, relates to a field of biomedical sciences. Particularly, but not exclusively, the present disclosure relates to devices used for microscopic analysis of biological fluids. Further, embodiments of the present disclosure relate to a cartridge employed for single step microscopic analysis of the biological fluids.

BACKGROUND OF THE DISCLOSURE

Historically, biologic fluid samples such as whole blood, urine, cerebrospinal fluid, body cavity fluids, etc., have had their particulate or cellular contents evaluated by smearing a small undiluted amount of the fluid on a slide and evaluating that smear under a microscope. Reasonable results can be gained from such a smear, but the cell integrity, accuracy and reliability of the data depends largely on the technician's experience and technique. Another technique for evaluating a biologic fluid sample involves diluting a volume of the sample, placing it within a chamber, and manually evaluating and enumerating the constituents within the diluted sample. Dilution is necessary if there is a high concentration of constituents within the sample, and for routine tests such as complete blood count tests, several different dilutions may be required. Different apparatuses which analyze various parameters of a sample are known, however the samples of a subject under evaluation needs to be sent to a laboratory and is a time-consuming process.

Point-of-care testing (POCT) is defined as medical testing at or near the site of patient care, for example at the doctor's office. Point of Care Testing systems enable quick performance of tests, for example blood tests, eliminating a need for sending samples to the laboratory. Quick obtaining of test results allows immediate clinical management decisions to be made. In general point-of-care testing (POCT) is performed by placing test samples in a cartridge and inserting the cartridge in a portable analysis machine. The cartridge is defined with multiple chambers where each chamber is designated with a functionality related to analysis of the sample. Some of the chambers may store reagents including but not limited to staining reagents, coagulation reagents and the like, required for analysis of the test samples. The test samples, after reacting with the reagents are analyzed in the portable analysis machine. Additionally, analysis such as, but not limited to, cell counting, cell identification and classification in the biological fluid may be performed by analyzing the biological fluid under stained or unstained condition. Whereas, analysis including, but not limited to, quantification of analytes in the biological fluid may be performed by various types of chemical analysis which require separate analysis chambers in the cartridges. Such cartridges are defined with multiple inlets to allow the biological fluid to each of the individual analysis chambers for analyzing each parameter of the biological fluid and obtaining a holistic result from the portable analysis machine. Each inlet of the analysis chambers may require a portion of the biological fluid which may require multiple samples of biological fluid from the subject for analysis. However, it may be exhausting and/or painful to the subject while extracting the biological fluid multiple times and in large amounts from the subject for analysis in multiple chambers of the cartridges. Further preparation of multiple samples by an operator is time-consuming and may involve operator errors.

The present disclosure is directed to overcome one or more limitations stated above or any other limitations associated with the conventional mechanisms.

SUMMARY OF THE DISCLOSURE

One or more shortcomings of the prior art are overcome by a method and a system as claimed and additional advantages are provided through the cartridge as claimed in the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

In one non-limiting embodiment of the present disclosure a cartridge for analysis of a biological fluid is disclosed. The cartridge comprises a base plate and an inlet. The base plate is defined with a flow surface. The inlet is configured to introduce the biological fluid to the base plate. The flow surface of the base plate comprises a first passage and a second passage extending from the first passage. The first passage is fluidly connected to the inlet and is configured to receive the biological fluid from the inlet. The first passage fluidly connects to a first analysis chamber. The second passage is configured to receive the biological fluid from the first passage. The second passage is in fluid connection with a reagent chamber, where the reagent chamber comprises a plurality of reagents to lyse, react and stain the biological fluid in a predetermined time. The second passage is configured to extend from the reagent chamber and fluidly connect to a second analysis chamber on the base plate, to receive stained biological fluid from the reagent chamber.

In an embodiment, the cartridge comprises a feed boot defined around circumference of the inlet configured to guide the biological fluid into the inlet.

In an embodiment, the second passage comprises a serpentine passage defined between the reagent chamber and the second analysis chamber, where the serpentine passage is configured to mix the plurality of reagents from the reagent chamber during flow of the biological fluid.

In an embodiment, the diameter of the serpentine passage is less than the diameter of the second passage for restricted flow of the biological fluid.

In an embodiment, the cartridge comprises a third analysis chamber connected between the serpentine passage and the second analysis chamber to delay the flow of the biological fluid to the second analysis chamber.

In an embodiment, the depth of the first analysis chamber is in a range of 10 to 50 microns, depth of second analysis chamber is 3 to 5 times to the depth of the first analysis chamber and depth of the third analysis chamber is 5 to 12 times to the depth of the second analysis chamber.

In an embodiment, the first analysis chamber allows imaging of the biological fluid by a first microscopic analysis, the second analysis chamber allows imaging of the biological fluid by a second microscopic analysis and wherein the third analysis chamber allows to analyze the biological fluid by a third microscopic analysis.

In an embodiment, the biological fluid is configured to flow from one end to another end of each of the first analysis chamber, the second analysis chamber and the third analysis chamber.

In an embodiment, flow of the biological fluid in the first analysis chamber, the second analysis chamber and the third analysis chamber is balanced by capillary force and an atmospheric pressure.

In an embodiment, the base plate is coated with a surface modification reagent to allow the biological fluid to flow on the flow surface by the capillary force.

In an embodiment, depth of the reagent chamber is in a range of 0.3 to 3 mm. In an embodiment, the plurality of reagents in the reagent chamber are in a semi-solid or gel form with viscosity in a range of 6 centipoise to 910 centipoise.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The novel features and characteristics of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

Figure la illustrates a top view of a cartridge in accordance with an embodiment of the present disclosure.

Figure lb illustrates a side view of the cartridge of Figure la, in accordance with an embodiment of the present disclosure.

Figure 1c is an isometric view of the cartridge in accordance with an embodiment of the present disclosure.

Figure Id is a top view depicting the first coverslip and the second coverslip of the cartridge attached on top of the cartridge in accordance with an embodiment of the present disclosure.

Figure 2a illustrates the top view of the cartridge with a reagent in the reagent chamber in accordance with an embodiment of the present disclosure.

Figure 2b illustrates the top view of the cartridge depicting two reagents in the reagent chamber in accordance with an embodiment of the present disclosure. Figure 2c is a top view of the cartridge defined with two reagent chambers with different reagents in each of the reagent chamber in accordance with an embodiment of the present disclosure.

The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the system and method illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION

While the embodiments in the disclosure are subject to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the figures and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.

The terms "comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusion, such that a device, assembly, mechanism, and system that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system, or assembly, or device. In other words, one or more elements in a system preceded by “comprises... a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or method.

Embodiments of the present disclosure discloses a cartridge for analysis of a biological fluid. The cartridge comprises a base plate and an inlet defined in the base plate. The base plate is defined with a flow surface. The inlet is configured to introduce the biological fluid to the base plate. The flow surface of the base plate comprises a first passage and a second passage extending from the first passage. The first passage is fluidly connected to the inlet and is configured to receive the biological fluid from the inlet. The first passage fluidly connects to a first analysis chamber. The second passage is configured to receive the biological fluid from the first passage. The second passage is in fluid connection with a reagent chamber, where the reagent chamber comprises a plurality of reagents to lyse, react and stain the biological fluid in a predetermined time. The second passage is configured to extend from the reagent chamber and fluidly connect to a second analysis chamber on the base plate, to receive stained biological fluid from the reagent chamber. With such configuration, the cartridge allows a single step analysis of various parameters of the biological fluid requiring minimal number of samples of the biological fluid from a subject under evaluation. The cartridge may eliminate or reduce need for trained operators and may be perfectly suited for point-of-care testing devices for testing biological fluids of the subject.

The disclosure is described in the following paragraphs with reference to Figures la to 2c. In the figures, the same element or elements which have same functions are indicated by the same reference signs. It is to be noted that, point of care testing device is not illustrated in the figures for the purpose of simplicity. One skilled in the art would appreciate that the device as disclosed in the present disclosure may be used for analysis of any biological fluid including but not liming to blood, urine, saliva, semen, and the like. The system and the method of the present disclosure may also be implemented in point-of-care testing devices that analyze biological fluids in a cartridge without deviating from the principles of the present disclosure.

Figure la and lb illustrate an exemplary embodiment of the present disclosure which illustrate a top view and a side view of a cartridge (100) for analysis of a biological fluid. The cartridge (100) may be configured to receive and contain a biological fluid including, but not limited to, blood, urine, saliva, semen and the like, for performing a plurality of analyses under a microscope [not shown in Figures] . The plurality of analyses may include analysis such as, but not limited to, RBC, HCT, MCV, ROW, PLT, HGB, MCH, MCHC, WBC & WBC differential count (NEUT %, LYMPH %, MONO %, EO %, BASO %, IG %) and the like when blood is considered as a biological fluid. The plurality of analyses may be varied based on the biological fluid under consideration and the same shall not be considered a limitation. In an embodiment, the shape of the cartridge (100) may be defined with either a rectangular, circular, square or a rhomboidal cross section and the same shall not be considered a limitation. The cartridge (100) may be inserted in a portable microscope or any other device [not shown in Figures] capable of analysing the biological fluid defined with a slot for insertion of the cartridge (100) for analysis of the biological fluid. The cartridge (100) may be made of a transparent material to suitably allow microscopic analysis of the biological fluid. The cartridge (100) may be configured to receive the biological fluid without requiring any additional preparation such as mixing of the biological fluid with a reagent in a separate container which may involve operator error with quantity of reagent being mixed with the biological fluid. The biological fluid may be mixed externally with a buffer only for dilution. Referring now to Figure lb in conjunction with Figure la and Figure 1c, the cartridge (100) includes a base plate (1) defined with a flow surface. In an embodiment, the flow surface may be etched or pre-moulded to be integrally defined on the base plate (1). The base plate (1) may be defined with at least two parallel major surfaces as can be seen in Figure 1c. The base plate (1) may be defined with a thickness, and the flow surface may be defined on one of the at least two parallel major surfaces as can be seen in Figures lb and 1c. The at least two parallel major surfaces of the base plate (1) may include a top major surface and a bottom major surface. For sake of explanation, the flow surface is depicted on the bottom major surface of the base plate (1). However, the flow surface may also be defined on the top major surface of the base plate ( 1 ) . The bottom maj or surface of the base plate ( 1 ) may be provided with a surface modification reagent or may be polished to allow smooth flow [i.e., without or with minimal turbulence] of biological fluids on the flow surface thereon. In an embodiment, the flow surface may be coated with a hydrophilic coating to allow smooth flow of the biological sample, however the same shall not be considered a limitation. The flow surface of the base plate (1) may be configured to receive and allow flow of fluids including, but not limited to, the biological fluids. In the illustrative embodiment, the flow surface of the base plate (1) may be defined at a top surface, which may be referred to a surface exposed to a lens of the microscope for analysis of the biological fluid as best seen in Figure la.

Referring again to Figure la, the cartridge (100) may be defined with an inlet (2) for introducing the biological fluid on the flow surface of the base plate (1). The inlet (2) may be defined proximal to one end of the base plate (1) to allow the biological fluid. In an embodiment, the inlet (2) may be defined with a circular cross section to allow the biological fluid. The cross section of the inlet (2) shall not be considered a limitation as a person skilled in the art may envisage various such cross sections of the inlet (2) without deviating from the scope of the present disclosure. The biological fluid may be introduced into the cartridge (100) through the inlet (2) by a convey means such as, but not limited to, a pipette, capillary tube, dropper and the like, which may be employable for introduction of the biological fluid into the cartridge (100). The biological fluid at the inlet (2) may constitute a high-pressure region, while the pressure within the cartridge (100) may be at the atmospheric pressure. Such difference in pressure at the inlet (2) and the cartridge (100) may enable movement of the biological fluid into the cartridge (100) as a result of capillary action. In an embodiment, the biological fluid may be diluted to a predefined concentration, for reducing viscosity of the biological fluid for smooth flow into the cartridge (100) for capillary action.

In an embodiment, the cartridge (100) may be defined with a feed boot (2’) defined around the circumference of the inlet (2) configured to guide the biological fluid to the inlet (2) as best seen in Figures lb and 1c. The feed boot (2’) may extend vertically from the top surface of the base plate (1) as best seen in Figure lb. At least a portion of the feed boot (2’) may be defined with a conical surface (depicted with dashed lines within the feed boot (2’) in the side view of Figure la) inclined about the vertical axis of the feed boot (2’) perpendicular to the top surface of the base plate (1). The feed boot (2’) may be defined with an opening at the bottom configured to guide the biological fluid toward the inlet (2). The conical surface of the feed boot (2’) may be configured to receive and store the biological fluid as a portion of the biological fluid flows to the inlet (2). In an embodiment, the opening of the feed boot (2’) may be fluidly connected to the inlet (2).

Referring again to Figures la and lb, the flow surface of the base plate (1) may include a first passage (3) and a second passage (5). The first passage (3) may be fluidly connected to the inlet (2) on one end to receive the biological fluid from the inlet (2). In the illustrative embodiment, the first passage (3) is defined with a tubular cross section. However, the first passage (3) may be defined with other cross sections such as, but not limited to, a square cross section, a rectangular cross section, a rounded square cross section and a rounded rectangular cross section to allow flow of the biological fluid. In the illustrative embodiment, the first passage (3) may extend parallel to the length of the cartridge (100). The first passage (3) may be fluidly connected to a first analysis chamber (4) positioned along the length of the cartridge (100). The first analysis chamber (4) may be defined on the flow surface of the base plate (1) defined with a depth. In an embodiment, the first analysis chamber (4) may be defined between the flow surface of the base plate (1) and a first coverslip (4’) fixedly positioned over the base plate (1) as seen in Figure Id. In an embodiment, the first analysis chamber (4) may be defined with at least two ends such as a first end (4a) and a second end (4b), where the biological fluid flows from the first end (4a) to the second end (4b). In the illustrative embodiment, the first end (4a) may be proximal to the first passage (3) and the second end (4b) may be distal to the first passage (3). The second end (4b) of the first analysis chamber (4) may be open to the atmosphere, allowing flow of the biological fluid in the first analysis chamber (4) based on the capillary force at the first end (4a) and the atmospheric pressure at the second end (4b). The capillary force at the first end (4a), the atmospheric pressure at the second end (4b) and depth of the first analysis chamber (4) may lead to formation of a first monolayer of the biological fluid within the first analysis chamber (4).

In an embodiment, the first analysis chamber (4) may be defined proximal and parallel to a first lateral edge of the rectangular cross section of the base plate (1) along the length of the base plate (1). The position of the base plate (1) within the flow surface of the base plate (1) is depicted for explanatory purposes only and the same shall not be considered a limitation. In an illustrative embodiment, depth of the first analysis chamber (4) may be in a range of 10 to 50 microns. The flow of the biological fluid in the first analysis chamber (4) may be in the form of a layer to allow analysis of the biological fluid by a first microscopic analysis. In the illustrative embodiment, the first analysis chamber (4) may allow analysis of the biological fluid by a first microscopic analysis without storing any reagent within. The first analysis chamber (4) may allow analysis of a first set of characteristic properties of the biological sample. For instance, the first analysis chamber (4) may allow analysis of Red Blood Cells (RBC) and platelets, when blood is considered as the biological fluid for analysis. However, the first analysis chamber (4) may optionally store at least one reagent to analyze the biological fluid.

Referring again to Figure la, the second passage (5) may extend from the first passage (3) and may be configured to receive the biological fluid from the first passage (3). The first passage (3) and the second passage (5) may be defined with the same diameter or varied diameter. In the illustrative embodiment, the second passage (5) is defined with a tubular cross section. However, the second passage (5) may be defined with other cross sections such as, but not limited to, a square cross section, a rectangular cross section, a rounded square cross section and a rounded rectangular cross section to allow flow of the biological fluid. In an embodiment, the second passage (5) may include at least two portions such as a first portion and a second portion. In the illustrative embodiment, the first portion of the second passage (5) may be extended perpendicular to the first passage (3) and the second portion of the second passage (5) may be extended parallel to the first passage (3). Diameter of the first passage (3) may be greater than the diameter of the second passage (5) and the same shall not be considered a limitation. The second passage (5) may be extending from a portion of the first passage (3) between the inlet (2) and the first analysis chamber (4). One end of the second passage (5) may be fluidly connected to the first passage (3) and another end opposite to the one end connected to the first passage (3) may be fluidly connected to a reagent chamber (7).

In an embodiment, the reagent chamber (7) may comprise a plurality of reagents configured to at least react, lyse and stain the biological fluid in a predetermined time upon receiving the biological fluid from the second passage (5). The plurality of reagents may be selected from a group consisting of at least one detection reagent, at least one lysing reagent, at least one dissolution agent, at least one standardization agent, at least one viscosity modulating reagent and at least one staining reagent. In an embodiment, the reagent chamber (7) may comprise plurality of sub-chambers configured to contain the plurality of reagents within the reagent chamber (7). The plurality of reagents may, when added to the biological fluid, react to produce change in characteristic properties such as, but not limited to, color, optical absorption, optical transmission, PH, refractive index and the like of the biological fluid. Such change in characteristic properties of the biological fluid may be quantified for a biochemical test. For example, the biochemical test may include, but may not be limited to, identifying the presence of analytes such as hemoglobin, glycated hemoglobin, lipids, antigens, antibodies, calcium, iron, sodium, potassium, magnesium, chloride, bicarbonate, and the like in the biological fluid.

For sake of illustration, the reagent chamber (7) is depicted with five sub-chambers for storing the plurality of reagents as best seen in Figure la. However, the number of sub-chambers in the reagent chamber (7) may be varied based on requirement. In the illustrative embodiment, the plurality of sub-chambers may be configured to store miniscule volume of the plurality of reagents, where the total volume of the plurality of reagents stored within the reagent chamber (7) may be less than 10 to 15 microliters to at least stain, react and lyse the biological fluid by allowing mixing of the biological fluid with the plurality of reagents in the reagent chamber (7). The quantity of the plurality of reagents in the reagent chamber (7) may be defined based on amount of the biological fluid being introduced into the cartridge (100). The depth of the reagent chamber (7) may be in a range of 0.3 to 3mm. In an embodiment, the plurality of reagents may be in a semi-solid state or a gel state within the reagent chamber (7) to restrict flow of the plurality of reagents within the sub-chambers of the reagent chamber (7) and allow instantaneous or near-instantaneous reaction of the plurality of reagents with the biological fluid. Further, concentration and viscosity of the plurality of reagents may be optimized such that the plurality of reagents may be restricted within the plurality of sub-chambers of the reagent chamber (7), to thereby avoid spillage of the plurality of reagents from the reagent chamber (7). In the illustrative embodiment, the viscosity of the plurality of reagents may be in the range of 6 centipoise to 910 centipoise.

In an embodiment, the reagent chamber (7) may be configured to receive the biological fluid from the second passage (5), where the biological fluid may be lysed, reacted and/or stained by the plurality of reagents in the reagent chamber (7). The plurality of reagents in the reagent chamber (7) may include plurality of nucleic acid and protein binding reagents. Different types of cells of the biological fluid may have different amounts of DNA, RNA, Protein, fragments of DNA granular structures and the like based on the biological fluid introduced into the cartridge (100). Accordingly, such cells absorb different quantities of the plurality of reagents specific to cell type. Thus, the microscopic analysis of cells based on morphology and color may be performed after the biological fluid may be stained in the reagent chamber (7). Since the plurality of reagents bound with nucleic acid and protein absorbs more intensely, the need for a separate washing step while analyzing the biological fluid in the proposed cartridge (100) may be eliminated.

Referring again to Figure la, the second passage (5) may include a serpentine passage (8) fluidly connected to the reagent chamber (7) and may be configured to receive the biological fluid from the reagent chamber (7). The serpentine passage (8) may be configured to allow mixing of the plurality of reagents with the biological fluid while the biological fluid flows through the serpentine passage (8). The serpentine passage (8) may be configured to allow proper mixing of the plurality of reagents with the biological fluid for microscopic evaluation of the biological fluid after mixing. In the illustrative embodiment, the serpentine passage (8) may be defined with plurality of bent flow surfaces on the flow surface of the base plate (1) as best seen in Figure la, where the biological fluid and the plurality of reagents may be mixed due to movement of the biological fluid along the serpentine passage (8). In an embodiment, the diameter of the serpentine passage (8) may be less than the diameter of the second passage

(5) to allow restricted flow of the biological fluid.

In an embodiment, the second passage (5) may be configured to extend from the reagent chamber (7) to a second analysis chamber (6). In the illustrative embodiment, the second analysis chamber (6) may be fluidly connected to the reagent chamber (7) through the serpentine passage (8) and may be configured to receive the stained biological fluid from the reagent chamber (7) after mixing in the serpentine passage (8). The second analysis chamber

(6) may be defined on the flow surface of the base plate (1) defined with a depth. In an embodiment, the second analysis chamber (6) may be defined between the flow surface of the base plate (1) and a second coverslip (6’) fixedly positioned over the base plate (1) as can be seen in Figure Id. In an embodiment, the second analysis chamber (6) may be defined with at least two ends such as a third end (6a) and a fourth end (6b), where the biological fluid flows from the third end (6a) to the fourth end (6b). In the illustrative embodiment, the third end (6a) may be defined on one end proximal to the second passage (5) and the fourth end (6b) may be distal to the second passage (5). The fourth end (6b) of the second analysis chamber (6) may be open to the atmosphere, thus allowing flow of the biological fluid in the second analysis chamber (6) balanced by the capillary force at the third end (6a) and the atmospheric pressure at the fourth end (6b). The balancing of the capillary force and the atmospheric pressure in the second analysis chamber (6) and the depth of the second analysis chamber (6) may lead to formation of a second monolayer of the biological fluid within the second analysis chamber (6). The second analysis chamber (6) may be positioned along the length of the base plate (1) and positioned below the first analysis chamber (4). The second analysis chamber (6) may be defined proximal to another end of the base plate ( 1 ) opposite to the one end being defined with the inlet (2).

In an embodiment, the second analysis chamber (6) may be defined proximal and parallel to a second lateral edge of the rectangular cross section of the base plate (1) and along the length of the base plate (1). The position of the second analysis chamber (6) within the flow surface of the base plate (1) is depicted for explanatory purposes only and the same shall not be considered a limitation. In an illustrative embodiment, depth of the second analysis chamber (6) may be 3 to 5 times to the depth of the first analysis chamber (4). The flow of the biological fluid in the second analysis chamber (6) may be in form of a layer to allow analysis of the stained biological fluid by a second microscopic analysis. In the illustrative embodiment, the second analysis chamber (6) may allow analysis of the biological fluid by the second microscopic analysis without storing any reagent within. The second analysis chamber (6) may allow analysis of a second set of characteristic properties of the biological sample. For instance, the second analysis chamber (6) may allow analysis of White Blood Cells and quantification of hemoglobin, when blood is considered as the biological fluid for analysis. However, the second analysis chamber (6) may optionally store at least one reagent to allow analysis of the stained biological fluid. In the illustrative embodiment, the cartridge (100) may include a third analysis chamber connected between the serpentine passage (8) and the second analysis chamber (6) to delay flow of the stained biological fluid to the second analysis chamber (6). In the illustrative embodiment, the third analysis chamber (9) (9) may be fluidly connected to the reagent chamber (7) through the serpentine passage (8) and may be configured to receive the stained biological fluid from the reagent chamber (7) after mixing in the serpentine passage (8). In an embodiment, the third analysis chamber (9) may be defined in a circular shape. The third analysis chamber (9) may be defined on the flow surface of the base plate (1) defined with a depth. In the illustrative embodiment, the third analysis chamber (9) may be defined proximal and parallel to a second lateral edge of the rectangular cross section of the base plate (1) connected below the serpentine passage (8). The position of the third analysis chamber (9) within the flow surface of the base plate (1) is depicted for explanatory purposes only and the same shall not be considered a limitation.

The flow of the biological fluid in the third analysis chamber (9) may be in the form of a thick layer defined with a thickness greater than thickness of the first monolayer and the second monolayer to allow analysis of the stained biological fluid by a third microscopic analysis. The thickness of the biological fluid in the third analysis chamber (9) may be varied based on the third microscopic analysis. In the illustrative embodiment, the third analysis chamber (9) may allow analysis of the biological fluid by the third microscopic analysis without storing any reagent within. The third analysis chamber (9) may allow analysis of a third set of characteristic properties of the biological sample. For instance, the third analysis chamber (9) may allow analysis of the third set of properties associated with optical density of the biological fluid such as hemoglobin when blood is considered as the biological fluid for analysis. However, the third analysis chamber (9) may optionally store at least one reagent to allow analysis of the stained biological fluid. In an illustrative embodiment, depth of the third analysis chamber (9) may be 5 to 12 times to the depth of the second analysis chamber (6) to allow appropriate quantity of the biological fluid for the third microscopic analysis. In an embodiment, the depth of the first analysis chamber (4), the second analysis chamber (6) and the third analysis chamber (9) may be varied based on the biological sample under analysis.

In an embodiment, the third analysis chamber (9) may be defined with at least two ends such as a fifth end (9a) and a sixth end (9b), where the biological fluid flows from the fifth end (9a) to the sixth end (9b). In the illustrative embodiment, the fifth end (9a) may be proximal to the serpentine passage (8) and the sixth end (9b) may be distal to the serpentine passage (8). The sixth end (9b) of the third analysis chamber (9) may be connected to the second analysis chamber (6), thus allowing flow of the biological fluid in the third analysis chamber (9) balanced by the capillary force at the fifth end (9a) and the sixth end (9b), thereby causing a delay in flow of the biological fluid to the second analysis chamber (6). In an embodiment, the biological fluid flows from the inlet (2) to the third analysis chamber (9) in the order of the second passage (5), the reaction chamber, the serpentine passage (8) while the biological fluid flows from the inlet (2) to the first analysis chamber (4) through the first passage (3) due to delay caused by the third analysis chamber (9).

Referring now to Figure Id which is atop view depicting the first coverslip (4’) and the second coverslip (6’) attached on top of the cartridge (100). In an embodiment, the inlet (2), the feed boot (2’), the first analysis chamber (4) and the second analysis chamber (6) may be defined on the top major surface of the cartridge (100), where the first passage (3), the second passage (5), the reagent chamber (7), the serpentine passage (8), and the third analysis chamber (9) may be defined on the bottom major surface of the cartridge (100) and may be covered by a rear cover (10) defined beneath the bottom major surface of the cartridge (100) to contain the biological fluid. The inlet (2), the feed boot (2’), the first analysis chamber (4) and the second analysis chamber (6) may be fluidly connected to the first passage (3), the second passage (5), the reagent chamber (7), the serpentine passage (8), and the third analysis chamber (9) along length or thickness of the base plate (1). The base plate (1) may be machined along the length or thickness to provide a flow path from the inlet (2), the feed boot (2’), the first analysis chamber (4) and the second analysis chamber (6) to the first passage (3), the second passage (5), the reagent chamber (7), the serpentine passage (8), and the third analysis chamber (9). The first coverslip (4’) and the second coverslip (6’) may be positioned over the first analysis chamber (4) and the second analysis chamber (6) and may be attached above the top major surface by an adhesive to thereby contain the biological fluid within the cartridge (100) between the rear cover (10) and the first coverslip (4’) and the second coverslip (6’) when the biological fluid is introduced through the inlet (1). In the illustrative embodiment, the first passage (3), the second passage (5), the reagent chamber (7), the serpentine passage (8), the first analysis chamber (4), the second analysis chamber (6) and the third analysis chamber (9) are integrally defined on the base plate (1) as best seen in Figure Id. Referring now to Figures 2a to 2c, the reagent chamber (7) may be configured to store the plurality of reagents, where a first reagent of the plurality of reagents may be filled in all the sub-chambers of the reagent chamber (7) as best seen in Figure 2a. The plurality of subchambers of the reagent chamber (7) may be configured to store at least two reagents of the plurality of reagents such as a first reagent in at least one sub-chamber of the plurality of subchambers and a second reagent in the at least one sub-chamber of the plurality of sub-chambers as can be seen in Figure 2b. In an embodiment, the cartridge (100) may be defined with two reagent chambers such as a first reagent chamber (7) and a second reagent chamber (7’). The first reagent chamber (7) may be configured to store a first reagent of the plurality of reagents and the second reagent chamber (7’) may be configured to store a second reagent of the plurality of reagents as best seen in Figure 2c.

In an embodiment, the proposed cartridge (100) does not require procedures such as reagent preparation/handling, mixing, and pipetting, except for dilution of the biological fluid by an operator and introducing the diluted biological fluid to the inlet (2). Such a configuration of the cartridge (100) may eliminate or reduce need for trained operators and may be perfectly suited for point-of-care testing devices fortesting biological fluids of the subject in a single step.

In an embodiment, the cartridge (100) may reduce the quantity of biological fluid required for testing and the operator may be required to collect the biological sample once from the subject, where the amount of biological fluid required may be in a range of 10 to 50 pL.

In an embodiment, the cartridge (100) may eliminate need for a skilled operator to handle the biological fluid while mixing the biological fluid with the plurality of reagents, where the operator may only be required for dilution and introducing the biological fluid into the cartridge (100). Further, the cartridge (100) may minimize or eliminate the error involved with the analysis results of the biological sample by reducing operator intervention.

In an embodiment, the cartridge (100) may eliminate over-staining and under-staining of the biological fluid by the plurality of reagents, since the reagent chamber (7) may be defined with a predetermined quantity of the plurality of reagents required for the analyses of the biological fluid.

EQUIVALENTS With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”

In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Referral Numeral:

Claims (12)

The Claim:

1. A cartridge (100) for analysis of a biological fluid, the cartridge (100) comprising: a base plate (1) defining a flow surface, the base plate (1) defining an inlet (2) for introducing the biological fluid, wherein the flow surface of the base plate (1) includes: a first passage (3) fluidly connected to the inlet (2), configured to receive the biological fluid from the inlet (2), wherein the first passage (3) fluidly connects to a first analysis chamber (4); and a second passage (5) extending from the first passage (3), the second passage (5) configured to receive the biological fluid from the first passage (3) and in fluid connection with a reagent chamber (7), wherein the reagent chamber (7) comprises a plurality of reagents to lyse, react and stain the biological fluid in a predetermined time; and wherein the second passage (5) is configured to extend from the reagent chamber (7) and fluidly connect to a second analysis chamber (6) on the base plate (1), to receive stained biological fluid from the reagent chamber (7).

2. The cartridge (100) as claimed in claim 1, comprises a feed boot (2’) defined around circumference of the inlet (2) configured to guide the biological fluid into the inlet (2).

3. The cartridge ( 100) as claimed in claim 1 , the second passage (5) comprises a serpentine passage (8) defined between the reagent chamber (7) and the second analysis chamber (6) configured to mix the plurality of reagents from the reagent chamber (7) during flow of the biological fluid.

4. The cartridge (100) as claimed in claim 3, wherein diameter of the serpentine passage (8) is less than diameter of the second passage (5) for restricted flow of the biological fluid.

5. The cartridge (100) as claimed in claim 3, comprises a third analysis chamber (9) connected between the serpentine passage (8) and the second analysis chamber (6) to delay the flow of the biological fluid to the second analysis chamber (6).

6. The cartridge (100) as claimed in claim 5, wherein depth of the first analysis chamber (4) is in a range of 10 to 50 microns, depth of the second analysis chamber (6) is 3 to 5 times to the depth of the first analysis chamber (4) and depth of the third analysis chamber (9) is 5 to 12 times to the depth of the second analysis chamber (6).

7. The cartridge (100) as claimed in claim 5, wherein the first analysis chamber (4) allows imaging of the biological fluid by a first microscopic analysis, the second analysis chamber (6) allows imaging of the biological fluid by a second microscopic analysis and wherein the third analysis chamber (9) allows to analyze the biological fluid by a third microscopic analysis.

8. The cartridge (100) as claimed in claim 5, wherein the biological fluid is configured to flow from one end to another end of each of the first analysis chamber (4), the second analysis chamber (6) and the third analysis chamber (9).

9. The cartridge (100) as claimed in claim 8, wherein flow of the biological fluid in the first analysis chamber (4), the second analysis chamber (6) and the third analysis chamber (9) is balanced by capillary force and an atmospheric pressure.

10. The cartridge (100) as claimed in claim 9, wherein the base plate (1) is coated with a surface modification reagent to allow the biological fluid to flow on the flow surface by the capillary force.

11. The cartridge (100) as claimed in claim 1, wherein depth of the reagent chamber (7) is in a range of 0.3 to 3 mm.

12. The cartridge (100) as claimed in claim 1, wherein the plurality of reagents in the reagent chamber (7) are in a semi-solid or gel form with viscosity in a range of 6 centipoise to 910 centipoise.