Method and analyzer for analyzing a blood sample - Patents.com

Abstract

A method for analyzing a blood sample is disclosed. The method includes disposing a cuvette with a sampling cavity and a sample analysis cavity on a rotatable member. The sampling cavity includes a blood sample to be analyzed. The method includes rotating the rotatable member at a first speed in a first rotation cycle for transfer of the blood sample from the sampling cavity to the sample analysis cavity. The method includes rotating the rotatable member at a second speed in a second rotation cycle after the first rotation cycle for separating blood portions from plasma in the blood sample. The method includes obtaining second absorbance data indicative of absorbance in the plasma during the second rotation cycle using a photometer. The method includes determining a second blood parameter, the plasma-free hemoglobin level of the blood sample, based on the second absorbance data. The method includes providing an output indicative of the second blood parameter.

Description

[Technical field]

[0001] The present disclosure relates to the field of blood analysis.The present disclosure relates to a method and an analyzer for analyzing a blood sample. [Background technology]

[0002] Hematology is the branch of medicine that covers diseases associated with blood and its components, including methods of treatment, diagnosis, analysis, etc. Hematology encompasses several different evaluations that can be performed on blood and / or blood components. One or more of the evaluations may require preparation of a blood sample prior to the actual evaluation.

[0003] Typical hematology analyses are performed in a laboratory setting and require transportation of the blood sample to the laboratory, so there is a significant time delay between receiving the blood sample and providing the analysis, which can delay necessary patient care. Summary of the Invention [Problem to be solved by the invention]

[0004] Thus, there is a need for accurate and fast hematology analysis to rapidly assess and analyze components of a patient's blood. In particular, there is a need for accurate and fast point-of-care hematology analysis. In particular, there is a need for accurate and fast point-of-care analysis of blood samples to determine levels of plasma free hemoglobin (PfHgb) in blood samples from patients supported by an extracorporeal membrane oxygenation device (ECMO) or a ventricular assist device (VAD). [Means for solving the problem]

[0005] A method for analyzing a blood sample is disclosed. The method includes disposing a cuvette with a sampling cavity and a sample analysis cavity on a rotatable member. The sampling cavity includes a blood sample to be analyzed. The method includes rotating the rotatable member at an initial speed in an initial rotation cycle prior to a first rotation cycle, the initial speed being insufficient for transfer of the blood sample from the sampling cavity to the sample analysis cavity. The method includes obtaining initial absorbance data indicative of absorbance in or through the sample analysis cavity of the cuvette during the initial rotation cycle using a photometer. The method includes determining a cuvette parameter associated with the cuvette based on the initial absorbance data. The method includes providing an output indicative of the cuvette parameter. The method includes rotating the rotatable member at a first speed, such as a first maximum speed, in the first rotation cycle for transfer of the blood sample from the sampling cavity to the sample analysis cavity. The method includes rotating the rotatable member at a second speed in a second rotation cycle after the first rotation cycle to separate blood portions from plasma within the blood sample. The method includes obtaining second absorbance data indicative of absorbance within the plasma using a photometer during or after the second rotation cycle. The method includes determining a second blood parameter, the plasma-free hemoglobin level of the blood sample, based on the second absorbance data. The method includes providing an output indicative of the second blood parameter.

[0006] It is an advantage of the present disclosure that the centrifugation of the blood sample and the analysis of the blood sample can be performed in a single method. Thereby, the time to perform the analysis may be reduced because the cuvette containing the blood sample does not need to be transported to a different device to perform the centrifugation and analysis of the body fluid sample. Furthermore, since the blood sample does not need to be transported between devices, such as between a centrifuge and an analysis unit, the risk of contamination of the blood sample may be reduced, thereby increasing the quality of the analysis. The method of the present disclosure further allows multiple blood parameters, such as total hemoglobin and plasma-free hemoglobin, to be determined in successive analysis cycles without the need to remove and / or replace the blood sample. Therefore, it is an important advantage of the present disclosure that the method can provide a fast and accurate analysis / hematology analysis of the blood sample. Furthermore, it is an important advantage that the method provides hematology results at the point of care, rather than having to transport the blood to a laboratory setting.

[0007] A blood analyzer is disclosed that includes a housing, a rotatable member, a photometer, and a controller. The rotatable member is rotatably disposed within the housing and includes a receptacle for receiving a cuvette that includes a sampling cavity and a sample analysis cavity. The receptacle can be an integral part of the rotatable member or a separate body attached to the rotatable member, depending on the use. When the receptacle is in the form of a separate body, it can be removed from the rotatable member for replacement or for easy cleaning. The sampling cavity of the cuvette contains a blood sample to be analyzed. The photometer is configured to acquire absorbance data associated with the sample analysis cavity of the cuvette. The controller is configured to rotate the rotatable member at an initial speed in an initial rotation cycle prior to a first rotation cycle, the initial speed being insufficient for transfer of the blood sample from the sampling cavity to the sample analysis cavity. The controller is configured to control the photometer to acquire initial absorbance data indicative of absorbance in the sample analysis cavity of the cuvette during the initial rotation cycle. The controller is configured to determine a cuvette parameter associated with the cuvette based on the initial absorbance data. The controller is configured to provide an output indicative of the cuvette parameter. The controller is configured to rotate the rotatable member at a first speed, such as a first maximum speed, in a first rotation cycle for transport of the blood sample from the sampling cavity to the sample analysis cavity. The controller is configured to rotate the rotatable member at a second speed in a second rotation cycle after the first rotation cycle for separating blood portions from plasma in the blood sample. The controller is configured to control the photometer to obtain second absorbance data during or after the second rotation cycle indicative of absorbance within the plasma of the separated blood sample. The controller is configured to determine a second blood parameter, the plasma-free hemoglobin level of the blood sample, based on the second absorbance data. The controller is configured to provide an output indicative of the second blood parameter.

[0008] It is an advantage of the present disclosure that the centrifugation of the blood sample and the analysis of the blood sample can be performed in a single analysis device, because the cuvette containing the blood sample does not need to be transported to a different device to perform the centrifugation and analysis of the blood sample. Thereby, the time to perform the analysis can be reduced. Furthermore, because the blood sample does not need to be transported between devices, such as between a centrifuge and an analysis unit, the risk of contamination of the blood sample can be reduced, thereby increasing the quality of the analysis. The analyzer of the present disclosure further enables multiple blood parameters, such as total hemoglobin and plasma-free hemoglobin, to be determined in successive analysis cycles without the need to remove and / or replace the body fluid sample. Therefore, it is an important advantage of the present disclosure that the analyzer can provide a fast and accurate analysis / hematology analysis of the blood sample. Furthermore, it is an important advantage of the analyzer that the analyzer provides point-of-care hematology results rather than having to transport the blood to a laboratory setting.

[0009] The above and other features and advantages of the present disclosure will become readily apparent to those skilled in the art from the following more detailed description of exemplary embodiments of the present disclosure, with reference to the accompanying drawings. [Brief description of the drawings]

[0010] [Figure 1A] FIG. 1 illustrates a method for analyzing a blood sample according to the present disclosure. [Figure 1B] FIG. 1 illustrates a method for analyzing a blood sample according to the present disclosure. [Figure 1C] FIG. 1 illustrates a method for analyzing a blood sample according to the present disclosure. [Figure 1D] FIG. 1 illustrates a method for analyzing a blood sample according to the present disclosure. [Diagram 2] FIG. 1 illustrates an analyzer for analyzing blood samples according to the present disclosure. [Diagram 3]FIG. 1 illustrates a photometer for analyzing blood samples according to the present disclosure. [Figure 4] FIG. 2 is a perspective view of an example cuvette according to the present disclosure. [Diagram 5] 1 is a schematic diagram of an example cuvette disclosed herein. [Figure 6] 1 is a schematic diagram of an example cuvette including cut lines showing a cross-sectional view of an example cuvette disclosed herein. [Figure 7] Figure 7A is a first schematic cut view of an example cuvette taken along section line AA as disclosed herein. Figure 7B is a first schematic cross-sectional view of an example cuvette taken along section line AA as disclosed herein. [Figure 8] Figure 8A is a second schematic cut view of an example cuvette taken along section line BB as disclosed herein. Figure 8B is a second schematic cross-sectional view of an example cuvette taken along section line BB as disclosed herein. [Figure 9] FIG. 2 is a third schematic cross-sectional view of an example cuvette taken along section line CC as disclosed herein. [Figure 10] FIG. 11 is a fourth schematic cross-sectional view of an example cuvette taken along section line DD as disclosed herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Various exemplary embodiments and details are described below with reference to the figures, when relevant. It should be noted that the figures may or may not be drawn to scale, and that elements of similar structure or function are indicated by similar reference numerals throughout the figures. It should also be noted that the figures are only intended to facilitate the description of the embodiments. The figures are not intended as an exhaustive description of the present disclosure or as a limitation on the scope of the present disclosure. Furthermore, the illustrated embodiment need not have all aspects or advantages shown. An aspect or advantage described in conjunction with a particular embodiment is not necessarily limited to that embodiment, and may be implemented in any other embodiment even if not so shown or explicitly described.

[0012] The figures are schematic and simplified for clarity, and the figures merely show details that aid in understanding the present disclosure, while other details are omitted. The same reference numerals are used throughout for identical or corresponding parts.

[0013] A method for analyzing a blood sample is disclosed. The method may be performed using a blood analyzer. A blood analyzer may be seen herein as an analytical device for analyzing blood.

[0014] The method includes disposing a cuvette on a rotatable member, the cuvette comprising a sampling cavity and a sample analysis cavity. In one or more example methods, for example, as further described herein and shown in Figures 4-10, the cuvette comprises a sampling cavity, a discharge cavity, and a sample analysis cavity. The sampling cavity contains a blood sample to be analyzed. The method can include disposing the cuvette such that an opening of the cuvette faces radially inward toward an axis of rotation of the rotatable member, and the sample analysis cavity of the cuvette is disposed radially outward from the sampling cavity of the cuvette.

[0015] In one or more example methods, the method may include rotating the rotatable member at an initial speed in an initial rotation cycle that is insufficient for the transfer of the blood sample from the sampling cavity to the sample analysis cavity. The initial speed may generate an initial centrifugal force acting on the blood sample during the initial rotation cycle, the initial centrifugal force being less than the capillary force acting on the blood sample in the sampling cavity. In other words, the initial speed is insufficient for the transfer of blood from the sampling cavity to the sample analysis cavity. Thereby, the blood sample will be retained in the sampling cavity during the initial rotation cycle. As such, the sample analysis cavity will remain empty, where empty means not containing blood. In one or more example methods, the initial rotation cycle is performed before the first rotation cycle.

[0016] In one or more example methods, the method can include obtaining initial absorbance data indicative of absorbance in or through a sample analysis cavity of the cuvette using a photometer and during an initial rotation cycle. Because a blood sample is held in the sampling cavity during the initial rotation cycle, the initial absorbance data can be absorbance data indicative of absorbance through an empty sample analysis cavity. Obtaining the initial absorbance data can include measuring the absorbance of the sample analysis cavity using one or more wavelengths, such as one, two, three, four, five, six, or more wavelengths.

[0017] In one or more example methods, the method can include determining cuvette parameters based on the initial absorbance data. The cuvette parameters can indicate a contamination level associated with the cuvette in one or more example methods. The contamination level associated with the cuvette can include, for example, indicate scratches on a surface, such as an inner and / or outer surface of the cuvette, discoloration of the cuvette, contamination of the cuvette, and / or any other imperfection of the cuvette in the area of ​​the sample analysis cavity of the cuvette. In other words, the contamination level associated with the cuvette can indicate defects of the cuvette, for example, of the material or surface of the cuvette, which may adversely affect the analysis of the blood sample. Contamination can be caused by blood, fingerprints, or other debris that is added to the area of ​​the sample analysis cavity, for example, due to incorrect handling of the cuvette by an operator. In one or more example methods, the cuvette parameters can indicate whether a cuvette from a previous analysis has been replaced or whether an already centrifuged cuvette is present in the analyzer. The cuvette parameters can indicate whether a cuvette is present in a receptacle, such as whether a cuvette is present in a receptacle, in one or more example methods. The cuvette parameters can indicate initial absorbance data for an empty cuvette, in one or more example methods.

[0018] In one or more example methods, the method includes providing an output indicative of the cuvette parameter. In one or more example methods, providing the output can include displaying a message to an operator indicative of the cuvette parameter. The message can, for example, indicate that a contamination level of the cuvette is equal to or greater than a predetermined contamination threshold or that the contamination level is less than a predetermined contamination threshold. A contamination level equal to or greater than a contamination threshold can indicate to an operator that analysis of the blood sample using the cuvette cannot be performed. A contamination level less than a contamination threshold can indicate to an operator that the operator can proceed with analysis of the blood sample using the cuvette. In one or more example methods, upon determining that the cuvette parameter is less than a cuvette detection threshold, providing the output can include displaying a message indicating that the cuvette is not detected. The cuvette detection threshold can be less than the contamination threshold. In one or more example methods, providing the output can include providing the cuvette parameter to a compensation function, which can compensate for the contamination level during subsequent measurement and determination of the blood parameter using the cuvette.

[0019] The method includes rotating the rotatable member at a first speed, such as a first maximum speed, in a first rotation cycle for transfer of the blood sample from the sampling cavity to the sample analysis cavity. The first speed, such as the first maximum speed, may be configured to create a first centrifugal force greater than a third capillary force generated by the sampling cavity of the cuvette. The first centrifugal force transfers the blood sample from the sampling cavity to the sample analysis cavity. In one or more example methods, the first rotation cycle is performed after an initial rotation cycle. Use of the terms "first speed" or "first rotation cycle" herein is used to identify individual elements, rather than suggesting any particular order associated with the "second" and "third" speeds and / or the "second" and "third" rotation cycles. In other words, in one or more example methods, the method may include a first rotation cycle without necessarily including a second rotation cycle, and may be rotated at a first speed without necessarily being rotated at a second speed. However, in one or more example methods that include multiple rotation cycles described herein, it may be beneficial to perform the rotation cycles according to an order indicated by "first," "second," and / or "third."

[0020] In one or more example methods, the method can include acquiring first absorbance data indicative of absorbance in the blood sample in the sample analysis cavity of the cuvette using a photometer and during or after the first rotation cycle. Acquiring the first absorbance data can include measuring the absorbance of the blood sample in the sample analysis cavity using two or more wavelengths, such as two, three, four, five, six, or more wavelengths.

[0021] In one or more example methods, the method includes determining a fill parameter indicative of a blood level, such as indicative of a fill level, such as indicative of an amount of blood, in the sample analysis cavity of the cuvette based on the first absorbance data. The fill parameter may indicate one or more of the following in one or more example methods: that the sample analysis cavity is underfilled, that the sample analysis cavity is improperly filled, and that the sample analysis cavity is correctly filled. In one or more example methods, the sample analysis cavity may be determined to be underfilled when the first absorbance data is less than a first blood level threshold. Too low a blood level, such as an underfilled cuvette, may cause the absorbance data to be lower than when the sample analysis cavity is correctly filled. A sample analysis cavity that is improperly filled may be viewed herein as not being filled with blood, such as being filled with a fluid other than blood.

[0022] In one or more example methods, the method includes providing an output indicative of the fill parameter, such as indicative of an amount of blood in a sample analysis cavity of the cuvette. In one or more example methods, the output can indicate that further analysis of the blood sample is not possible, such as when the fill parameter indicates that the cuvette is underfilled and / or improperly filled. In one or more example methods, the output can indicate that further analysis of the blood sample is possible, such as when the fill parameter indicates that the cuvette is properly filled. In one or more example methods, the output can be a signal that prevents further analysis of the blood sample, such as when the fill parameter indicates that the cuvette is underfilled and / or improperly filled. In one or more example methods, the output can be a signal that allows further analysis of the blood sample, such as when the fill parameter indicates that the cuvette is properly filled.

[0023] In one or more example methods, the method may include determining a first blood parameter, which is a total hemoglobin level of the blood sample, based on the first absorbance data. In one or more example methods, the total hemoglobin level may be determined by measuring an isosbestic wavelength between oxyhemoglobin (HbO2) and deoxyhemoglobin (Hb) and a compensation wavelength for unaltered whole blood or plasma. In one or more example methods, the total hemoglobin level may be determined without measuring an isosbestic wavelength between oxyhemoglobin (HbO2) and deoxyhemoglobin (Hb) by measuring using an additional wavelength and calculating the ratio of the measured wavelengths.

[0024] In one or more example methods, the method includes providing an output indicative of the first blood parameter, such as an indication of a total hemoglobin level. Providing the output can include providing the output to a display for indicating the total hemoglobin level to an operator.

[0025] The method includes rotating the rotatable member at a second speed, such as a second maximum speed, in a second rotation cycle to separate blood portions from plasma within the blood sample. The second rotation cycle may be performed after the first rotation cycle. The blood portions may be, for example, one or more of blood cells (such as red blood cells and / or white blood cells), fibrinogen, buffy coat, and lipids. In other words, the blood portions separated from the plasma may be one or more of blood cells, red blood cells, white blood cells, fibrinogen, buffy coat, and lipids. In one or more example methods, the second speed, such as the second maximum speed, is faster than the first speed, such as the first maximum speed. In one or more example methods, the second speed, such as the second maximum speed, may be equal to the first speed, such as the first maximum speed, and the second rotation cycle may be longer than the first rotation cycle. In other words, to separate blood portions from plasma, the rotatable member may be rotated at a second speed that is faster than the first speed or during a second rotation cycle that is longer than the first rotation cycle. The use of the term "second speed" or "second rotation cycle" herein is used to identify individual elements, rather than implying any particular order associated with the "first" and "third" speeds and / or the "first" and "third" rotation cycles. In other words, in one or more example methods, the method may include a second rotation cycle without necessarily including a first rotation cycle, and may be rotated at a second speed without necessarily being rotated at a first speed. However, in one or more example methods including multiple rotation cycles described herein, it may be beneficial to perform the rotation cycles according to the order indicated by "first", "second", and / or "third".

[0026] Fibrinogen is a glycoprotein complex made in the liver that circulates in the blood. During tissue and vascular injury, fibrinogen can be enzymatically converted by thrombin to fibrin and then to a fibrin-based clot. The fibrin clot functions primarily to occlude blood vessels to stop bleeding. The buffy coat is the part of an anticoagulated blood sample that contains most of the white blood cells and platelets following centrifugation of the blood sample. Lipids are fats found in blood.

[0027] The method includes acquiring second absorbance data during or after the second rotation cycle using a photometer. The second absorbance data is indicative of absorbance within the plasma. Acquiring the second absorbance data can include measuring absorbance of the plasma in the sample analysis cavity using two or more wavelengths, such as two, three, four, five, six, or more wavelengths.

[0028] The method includes determining a second blood parameter based on the second absorbance data. The second blood parameter is a plasma-free hemoglobin (PfHgb) level of the blood sample. In one or more example methods, the second absorbance data, such as a plasma-free hemoglobin level, can be continuously acquired during the second rotation cycle to detect when all, e.g., substantially all, blood cells have left the measuring eye and the remaining sample material is substantially pure plasma (possibly with free hemoglobin), and the photometer detects a stable detection signal, such as a signal indicative of stable, e.g., unchanged absorbance data. During the second rotation cycle, blood fractions, such as plasma and one or more of blood cells, fibrinogen, buffy coat, and lipids, will continuously separate from one another, causing the acquired absorbance data to continuously change. When the blood fractions, such as the plasma and one or more of blood cells, fibrinogen, buffy coat, and lipids, are completely separated, the absorbance data will stop changing and stable absorbance data can be detected. Thus, the stable absorbance data indicates that the separation is completed. Upon detecting that the detection signal, such as the acquired second absorbance data, is stable, the acquired PfHgb level can be presented. Upon detecting that the detection signal is stable, the acquisition of the second absorbance data can be terminated. Terminating the acquisition of the second absorbance data can include one or more of stopping the second rotation cycle, reducing the speed of the second rotation cycle, acquiring the third absorbance data and / or the first imaging data, and proceeding with another rotation cycle, such as the third rotation cycle described herein. By terminating the acquisition of the second absorbance data upon detecting that the detection signal is stable, the turnaround time (TAT) of the analysis can be reduced compared to when a predetermined measurement time is used.

[0029] The rotational cycles defined herein may be defined, in one or more example ways, by the maximum speeds allowed during each rotational cycle. For example, the initial maximum speed may be lower than a first maximum speed, which is lower than a second maximum speed, which is in turn lower than a third maximum speed. However, speeds, such as the rotational speed of a rotatable member, may vary during each respective rotational cycle.

[0030] In one or more example methods, the rotatable member may be stopped during different rotation cycles, such as the initial rotation cycle, the first rotation cycle, the second rotation cycle, and / or the third rotation cycle. In other words, the different rotation cycles may be separated by periods during which the rotatable member is stationary. As such, rotation of the rotatable member may be interrupted during the rotation cycles.

[0031] In one or more example methods, the rotatable member can transition between different rotational cycles, such as an initial rotational cycle, a first rotational cycle, a second rotational cycle, and / or a third rotational cycle, without stopping. In other words, the rotatable member can transition between different rotational cycles while continuously rotating. As such, the initial rotational cycle, the first rotational cycle, the second rotational cycle, and / or the third rotational cycle can be viewed as sub-cycles within one continuous rotational cycle.

[0032] The method includes providing an output indicative of the second blood parameter. In one or more example methods, providing the output can include providing instructions to an operator, the instructions indicative of the second blood parameter, such as a PfHgb level of the blood sample. Providing the instructions can include displaying a message to the operator indicative of the PfHgb level.

[0033] In one or more example methods, the method can include acquiring third absorbance data during the second rotation cycle using a photometer. The third absorbance data can be indicative of a separation time of red blood cells from plasma. Acquiring the third absorbance data can include measuring the absorbance of the blood sample in the sample analysis cavity using two or more wavelengths, such as two, three, four, five, six, or more wavelengths.

[0034] In one or more example methods, the method can include determining a third blood parameter, which is an erythrocyte sedimentation rate (ESR) of the blood sample based on the third absorbance data and the first absorbance data. ESR is a type of blood test that measures how quickly red blood cells, also called erythrocytes, settle to the bottom of a test tube, such as a cuvette, that contains the blood sample. Normally, red blood cells sediment relatively slowly. A faster than normal rate may indicate inflammation in the body. Inflammation is part of the immune response system. Inflammation can be a response to infection or injury.

[0035] In one or more example methods, the method can include providing an output indicative of the third blood parameter. In one or more example methods, providing the output can include providing instructions to an operator of the blood analyzer. Providing the instructions can include displaying a message to the operator indicative of the third blood parameter. The message can indicate, for example, that the ESR is above or below an ESR threshold. The ESR threshold can be an ESR indicative of a normal ESR, such as an ESR range, for a healthy person.

[0036] In one or more example methods, the method can include acquiring first image data after the second rotation cycle using an imaging device. Acquiring the first image data can include capturing the first image data using an imaging device. The first image data can be indicative of an image of at least a portion of the blood sample in the sample analysis cavity, such as an interface between separated blood cells and separated plasma of the blood sample. The first image data can be indicative of a position of the interface along a length of the sample analysis cavity, such as a percentage position along the length of the sample analysis cavity. The imaging device can be a camera.

[0037] In one or more example methods, the method can include determining a fourth blood parameter based on the first image data. The fourth blood parameter can be a hematocrit level of the blood sample. To determine the hematocrit level, the first image data should be indicative of at least a portion of the blood sample where an interface between blood plasma (such as blood plasma) on the one hand and red blood cells on the other hand is expected. The first imaging (imaging) data can indicate a location of an interface between separated red blood cells and blood plasma within the sample analysis cavity. In one or more example methods, such an interface is expected within 30-60% of the length of the sample analysis cavity. In one or more example methods, the hematocrit level can be determined based on the location of the interface, and a percent location of the interface along the length of the sample analysis cavity can indicate a percent level of hematocrit. A lower or higher hematocrit level with the same PfHgb concentration can indicate a more serious patient condition that may require further medical testing.

[0038] In one or more example methods, the method can include providing an output indicative of the fourth blood parameter.

[0039] In one or more example methods, the method can include rotating the rotatable member at a third speed, such as a third maximum speed, in a third rotation cycle, where the third speed, such as the third maximum speed, is faster than the first speed, such as the first maximum speed, the second speed, such as the second maximum speed, and the initial speed, such as the initial maximum speed. The third rotation cycle can be performed after the second rotation cycle. The third speed can be configured to induce a drop in fragile red blood cells. The use of the term "third speed" or "third rotation cycle" herein is used to identify individual elements, rather than implying any particular order related to the "first" and "second" speeds and / or the "first" and "second" rotation cycles. In other words, in one or more example methods, the method can include a third rotation cycle without necessarily including the first and / or second rotation cycles, and can be rotated at the third speed without necessarily being rotated at the first and / or second speeds. However, in one or more example methods including multiple rotation cycles described herein, it may be beneficial to perform the rotation cycles according to an order indicated by "first," "second," and / or "third."

[0040] In one or more example methods, the method can include acquiring fourth absorbance data indicative of absorbance in the blood sample in the sample analysis cavity of the cuvette using the photometer and during the third rotation cycle. Acquiring the fourth absorbance data can include measuring the absorbance of the blood sample in the sample analysis cavity using two or more wavelengths, such as two, three, four, five, six, or more wavelengths.

[0041] In one or more example methods, the method can include determining a fifth blood parameter based on the fourth absorbance data. The fifth blood parameter can be a second plasma-free hemoglobin level indicative of fragile blood cells of the blood sample. A difference between the second plasma-free hemoglobin level and the first plasma-free hemoglobin level indicates a level of fragile red blood cells, which may also be referred to as irithrocyte fragility or irithrocyte mechanical fragility, in the blood sample. The level of fragile red blood cells can indicate additional medical diseases, such as sickle cell or thalassemia.

[0042] In one or more example methods, the method includes providing an output indicative of the fifth blood parameter. In one or more example methods, providing the output can include displaying a message to an operator indicative of the fifth blood parameter. The message can, for example, indicate the fifth blood parameter and provide an indication to the operator that further medical testing is required, such as for a disease such as sickle cell and / or thalassemia.

[0043] In one or more example methods, instead of providing an erroneous result, an error code may be indicated to an operator when an obtained absorbance level indicates a hematocrit level that is too high. This may be the case, for example, when the amount of blood cells is so high that it is not possible to obtain a sufficient amount of plasma, thereby resulting in undesirable blood cells in the area of ​​the sample analysis cavity of the cuvette that is covered by the photometer.

[0044] In one or more example methods, the method may include detecting various types of incorrectly filled cuvettes and / or air bubbles in the blood sample based on one or more of the initial absorbance data, the first absorbance data, the second absorbance data, the third absorbance data, the first image data, and the fourth absorbance data. In one or more example methods, the method may include determining a blood level parameter indicative of a blood level, such as indicative of a fill level, in a sample analysis cavity of the cuvette based on the first absorbance data. The blood level parameter may in one or more example methods indicate one or more of the sample analysis cavity being underfilled, the sample analysis cavity being overfilled, and the sample analysis cavity being correctly filled.

[0045] In one or more example methods, obtaining the initial absorbance data, the first absorbance data, the second absorbance data, the third absorbance data, and / or the fourth absorbance data includes measuring absorbance using one, two, or more than two wavelengths, for example, three wavelengths, four wavelengths, five wavelengths, six wavelengths, or more. The wavelengths may be selected from a range between 300 nm and 1000 nm. In one or more example methods, the wavelengths may be two or more of 355 nm, 360 nm, 365 nm, 385 nm, 390 nm, 392 nm, 451 nm, 452 nm, 455 nm, 584 nm, 585 nm, 590 nm, 655 nm, and 860 nm. However, other wavelengths selected from the ranges shown above may also be used.

[0046] In one or more example methods, the absorbance data may be measured using a first wavelength, a second wavelength, a third wavelength, and a fourth wavelength. In one or more example methods, the first wavelength is 585 nm, the second wavelength is 860 nm, the third wavelength is 385 nm, and the fourth wavelength is 655 nm. In one or more example methods, the first wavelength is 585 nm, the second wavelength is 860 nm, the third wavelength is 455 nm, and the fourth wavelength is 655 nm.

[0047] In one or more example methods, obtaining the initial absorbance data, the first absorbance data, the second absorbance data, the third absorbance data, or the fourth absorbance data includes measuring absorbance during multiple rotations of the rotatable member.

[0048] In one or more example methods, determining one or more of the first blood parameter, the second blood parameter, the third blood parameter, the fourth blood parameter, the fifth blood parameter, and the cuvette parameter includes integrating absorbance data acquired during multiple rotations of the rotatable member.

[0049] When measuring at high rotational speeds of the rotating member, there is a very short time during each revolution during which the cuvette is in the light path of the photometer. Therefore, there is a limited time during each revolution during which the photometer can acquire absorbance data from the cuvette and / or from the blood sample in the cuvette. To ensure that sufficient absorbance data is acquired to analyze the blood sample, the measurement data from subsequent revolutions may be stored and integrated over multiple revolutions. Thus, the more revolutions of the rotatable member, the larger the signal that may be acquired. Once a sufficient signal has been acquired over multiple revolutions, the integration may be stopped and digitization, such as analog-to-digital (A / D) conversion, may be performed to obtain an intensity value, such as an absorbance value, of the measurement.

[0050] The initial spin cycle, the first spin cycle, the second spin cycle, and / or the third spin cycle may be performed sequentially, such that multiple blood parameters, such as first, second, third, fourth, and / or fifth blood parameters, such as plasma-free hemoglobin, total hemoglobin, sedimentation rate, etc. of whole blood in such a system may be obtained in sequential analyses using a single blood sample, thus providing faster and more accurate results.

[0051] A blood analyzer is disclosed. The blood analyzer includes a housing, a rotatable member, a photometer, and a controller. In one or more example blood analyzers, the blood analyzer can include a display configured to visually provide information to an operator of the blood analyzer, such as for visually displaying information indicative of a cuvette parameter, a first blood parameter, a second blood parameter, a third blood parameter, a fourth blood parameter, and / or a fifth blood parameter. In one or more example blood analyzers, the blood analyzer can include a drive unit, such as an electric motor, for driving, e.g., rotating, the rotatable member.

[0052] The housing can be a unitary housing that can house any and / or all of the modules discussed herein, such as the rotatable members, the photometer, the controller, the display, and / or the drive unit.

[0053] The housing can be plastic, metal, ceramic, etc., or a combination thereof, and the particular material of the housing is not limiting. The housing can include one or more ports. The housing can include one or more slots. The housing can include one or more vents. The housing can be a frame for holding different modules, such as multiple portions of a hematology analyzer.

[0054] The rotatable member is rotatably disposed within the housing. The rotatable member may be rotatably disposed about an axis of rotation. The rotatable member comprises a receptacle for receiving a cuvette. The receptacle may be an integral part of the rotatable member or may be a separate body attached to the rotatable member, depending on the use. If the receptacle is in the form of a separate body, it may be detached from the rotatable member for replacement or for easy cleaning. In one or more example analyzers, the receptacle may be configured to receive a cuvette having a particular shape or form. In one or more example analyzers, the receptacle may be selected from a plurality of different receptacles for receiving a respective type of cuvette. In one or more example analyzers, the rotatable member may be detached from the analyzer for replacement or for easy cleaning. In one or more example analyzers, the rotatable member may be selected from a plurality of rotatable members with different receptacles for receiving a respective type of cuvette. The cuvette may comprise a sampling cavity and a sample analysis cavity, the sampling cavity of the cuvette containing the blood sample to be analyzed. The rotatable member may be a circular member such as a disk. The receptacle may be positioned on the rotatable member at a distance r from the axis of rotation such that the centrifugal force F=mω 2 r is applied to a cuvette placed in a receptacle, where m is the mass of the cuvette, r is the distance from the axis of rotation of the rotating member, and ω is the angular velocity, such as the rate at which the rotating member rotates.

[0055] The analyzer may include a drive unit, such as an electric motor, for rotating the rotatable member. The controller may be configured to control the drive unit to control the speed of the rotatable member. In one or more example blood analyzers, the controller may include a computer program product. The computer program product may include a non-transitory computer-readable medium. The non-transitory computer-readable medium may have a computer program thereon. The computer program may include program instructions. The computer program may be loaded into a data processing unit. The computer program may be configured, for example, to cause the execution of the steps, processes, and / or modules discussed above when the computer program is executed by the data processing unit.

[0056] The rotatable member can include a measuring eye, such as an aperture, to allow light, such as light from a light source, to pass through the rotatable member. The aperture can be positioned in the receptacle to overlap the sample analysis cavity of the cuvette when the cuvette is placed in the receptacle. In one or more example analyzers, the rotatable member can include a blanking hole for measuring the intensity of a light source, such as an LED. The blanking hole can be a through hole positioned in the rotatable member to allow light from the light source to pass through the rotatable member to the photometer. The blanking hole can be positioned at the same radial distance from the center of rotation of the rotatable member as the measuring eye, but with an angular displacement. In one or more example analyzers, the blanking hole can be positioned 180 degrees displaced from the measuring eye. This allows the photometer to alternately measure the intensity of the sample analysis cavity and the light source at equal time intervals. By measuring the intensity of the light source through the blanking holes, drift in the light intensity of the light source can be detected and used to compensate for the drifting light intensity during measurements on the sample analysis cavity.

[0057] The photometer can be a multi-wavelength photometer. The photometer can include multiple light sources, such as two or more light sources, for emitting light at respective wavelengths, and one or more optical sensors, such as photodiodes, for measuring how much light is absorbed by an object located between the multiple light sources and the one or more optical sensors. The multiple light sources and the one or more optical sensors can be disposed on opposite sides of the rotatable member, such that light emitted from the light sources passes through an opening in the rotatable member and a cuvette disposed in a receptacle of the rotatable member before reaching the optical sensor. In other words, the multiple light sources can be disposed on a first side of the rotatable member, and the one or more optical sensors can be disposed on a second side of the rotatable member. The first side of the rotatable member and the second side of the rotatable member can be opposite sides of the rotatable member. The photometer can include a respective optical sensor for each of the light sources, or can include one optical sensor for the multiple light sources. In one or more example blood analyzers, the multiple light sources, such as two or more light sources, are Light Emitting Diodes (LEDs). In one or more example blood analyzers, the photometer can include a plurality of first light guides for directing light emitted by the plurality of light sources to the cuvette and one or more second light guides for directing light passing through the cuvette to one or more optical sensors. In one or more example blood analyzers, the photometer includes at least two light sources and at least two corresponding optical sensors, each light source emitting light at a different wavelength.

[0058] The photometer is configured to obtain, eg, measure, absorbance data associated with the sample analysis cavity of the cuvette.

[0059] In one or more example blood analyzers, the blood analyzer includes a display for displaying, eg, visually providing, information to an operator of the blood analyzer.

[0060] Therefore, an advantage of the analyzer disclosed herein is that centrifugation of the blood sample and analysis of the blood sample can be performed in a single device, thereby reducing the time to perform the analysis. Furthermore, since the blood sample does not need to be transported between devices, such as between a centrifuge and an analysis unit, the risk of contamination of the blood sample can be reduced, thereby increasing the quality of the analysis.

[0061] The controller is configured to rotate the rotatable member at a first speed, such as a first maximum speed, in a first rotation cycle for transfer of the blood sample from the sampling cavity to the sample analysis cavity. The controller may be configured to control the drive unit to rotate the rotatable member at a first speed, such as the first maximum speed. The first speed, such as the first maximum speed, may be configured to create a first centrifugal force that is greater than a capillary force generated by the sampling cavity of the cuvette. The capillary force of the sampling cavity is referred to herein as a third capillary force associated with the cuvette described herein. The first centrifugal force transfers the blood sample from the sampling cavity to the sample analysis cavity.

[0062] The controller may be configured to control the photometer to obtain first absorbance data indicative of absorbance in the blood sample in the sample analysis cavity of the cuvette during a first rotation cycle. The controller may be configured to obtain the first absorbance data by controlling the photometer to measure the absorbance of the blood sample in the sample analysis cavity using two or more wavelengths, such as two, three, four, five, six, or more wavelengths.

[0063] The controller may be configured to determine a first blood parameter, which is a total hemoglobin level of the blood sample, based on the first absorbance data. The controller may be configured to determine the total hemoglobin level by measuring an isosbestic wavelength between oxyhemoglobin (HbO2) and / or deoxyhemoglobin (Hb) and / or a compensation wavelength for unaltered whole blood or plasma using a photometer. In one or more example analyzers, the controller may be configured to determine the total hemoglobin level by measuring using additional, e.g., multiple, wavelengths and by calculating a ratio of the measured wavelengths. Thus, in one or more example analyzers, the controller may be configured to determine the total hemoglobin level without measuring an isosbestic wavelength between oxyhemoglobin (HbO2) and deoxyhemoglobin (Hb).

[0064] In one or more example blood analyzers, the controller is configured to provide an output indicative of the first blood parameter.

[0065] The controller is configured to rotate the rotatable member at a second speed, such as a second maximum speed, in a second rotation cycle after the first rotation cycle to separate blood portions from plasma within the blood sample. The blood portions separated from the plasma can be one or more of blood cells, red blood cells, white blood cells, fibrinogen, buffy coat, and lipids.

[0066] The controller is configured to control the photometer to obtain second absorbance data indicative of absorbance within the plasma of the separated blood sample during the second rotation cycle. The controller may be configured to control the photometer to obtain the second absorbance data by measuring the absorbance of the plasma in the sample analysis cavity using two or more wavelengths, such as two, three, four, five, six, or more wavelengths.

[0067] The controller is configured to determine a second blood parameter based on the second absorbance data. The second blood parameter can be a plasma-free hemoglobin level (PfHgb) of the blood sample. The controller can be configured to detect when all blood cells have left the measuring eye by being configured to detect that a stable detection signal, such as stable second absorbance data, is provided from the photometer, such as a signal indicative of stable, e.g., unchanged, absorbance data.

[0068] In one or more example analyzers, the controller may be configured to control the photometer and / or rotatable member to continuously acquire second absorbance data during the second rotation cycle to detect when all, e.g., substantially all, blood cells have left the measuring eye and the remaining sample material is substantially pure plasma (possibly with free hemoglobin). Upon detecting that a detection signal, such as the acquired second absorbance data, is stable, e.g., unchanged, the controller may be configured to provide an acquired PfHgb level. Upon detecting that the detection signal is stable, the controller may be configured to terminate acquisition of the second absorbance data. Terminating acquisition of the second absorbance data may include one or more of stopping the second rotation cycle, reducing the speed of the second rotation cycle, acquiring third absorbance data and / or the first imaging data, and proceeding with another rotation cycle, such as the third rotation cycle described herein. By terminating acquisition of the second absorbance data upon detecting that the detection signal is stable, the turnaround time (TAT) can be reduced compared to the time that can be achieved when a predetermined measurement time is used.

[0069] The controller is configured to provide an output indicative of the second blood parameter. In one or more example methods, the controller may be configured to control the display unit to provide instructions to an operator indicative of the second blood parameter, such as a PfHgb level.

[0070] In one or more example blood analyzers, the controller is configured to rotate the rotatable member at an initial speed in an initial rotation cycle that is insufficient for transport of the blood sample from the sampling cavity to the sample analysis cavity.

[0071] In one or more example hematology analyzers, the controller is configured to control the photometer to acquire initial absorbance data indicative of absorbance in the sample analysis cavity of the cuvette during an initial spin cycle. In one or more example hematology analyzers, the controller is configured to perform the initial spin cycle prior to the first spin cycle.

[0072] In one or more example hematology analyzers, the controller is configured to determine a cuvette parameter that is, e.g., indicative of, a contamination level associated with the cuvette based on the initial absorbance data. The contamination level associated with the cuvette can include scratches on a surface of the cuvette, discoloration of the cuvette, or contamination of the cuvette within an area of ​​the sample analysis cavity of the cuvette.

[0073] In one or more example blood analyzers, the controller is configured to provide an output indicative of the cuvette parameters. The controller may be configured to provide an output indicative of the cuvette parameters to a display for displaying a message indicative of the cuvette parameters to an operator. The controller may be configured to display a message indicating that the contamination level of the cuvette is equal to or greater than a predetermined contamination threshold or that the contamination level is less than a predetermined contamination threshold. A contamination level equal to or greater than the contamination threshold may indicate to an operator that analysis of the blood sample using the cuvette cannot be performed. A contamination level less than the contamination threshold may indicate to an operator that the operator may proceed with analysis of the blood sample using the cuvette.

[0074] In one or more example blood analyzers, the controller can provide an output indicative of the cuvette parameters to a compensation function, which can compensate for the contamination level during subsequent measurement and determination of the blood parameters using the cuvette.

[0075] In one or more example hematology analyzers, the controller is configured to control the photometer to obtain third absorbance data during the second rotation cycle indicative of a separation time of red blood cells from plasma in the sample analysis cavity of the cuvette. The controller may be configured to obtain the third absorbance data by being configured to control the photometer to measure the absorbance of the blood sample in the sample analysis cavity using two or more wavelengths, such as two, three, four, five, six, or more wavelengths.

[0076] In one or more example blood analyzers, the controller is configured to determine a third blood parameter, e.g., indicative of, the ESR of the blood sample in the sample analysis cavity of the cuvette, based on the third absorbance data and the first absorbance data.

[0077] In one or more example blood analyzers, the controller is configured to provide an output indicative of the third blood parameter. The controller may be configured to provide an output indicative of the third blood parameter to a display for displaying a message indicative of the third blood parameter to an operator. The controller may be configured to control the display to display a message indicative of the ESR being above or below an ESR threshold. The ESR threshold may be an ESR indicative of a normal ESR, such as an ESR range, for a healthy person.

[0078] In one or more example blood analyzers, the analyzer includes an imaging device, such as a camera, and the controller can be configured to control the imaging device to obtain a first image indicative of an image of at least a portion of the blood sample in the sample analysis cavity of the cuvette after the second rotation cycle.

[0079] In one or more example blood analyzers, the controller is configured to determine a fourth blood parameter that is, for example, indicative of, a hematocrit level of the blood sample based on the first image data.

[0080] In one or more example hematology analyzers, the controller is configured to provide an output indicative of the fourth blood parameter. The controller may be configured to provide an output indicative of the hematocrit level to a display for displaying a message indicative of the fourth blood parameter to an operator. In one or more example hematology analyzers, the output may be an error code. Instead of outputting an erroneous result, the controller may be configured to present an error code when the fourth blood parameter is greater than a hematocrit threshold. The hematocrit threshold may indicate, for example, an amount of blood cells at which it is not possible to obtain a sufficient amount of plasma, thereby resulting in undesirable blood cells in the measuring eye.

[0081] In one or more example blood analyzers, the controller is configured to rotate the rotatable member at a third speed in a third rotation cycle, the third speed being faster than the first speed, the second speed, and the initial speed. The controller can be configured to perform the third rotation cycle after the second rotation cycle.

[0082] In one or more example hematology analyzers, the controller is configured to control the photometer to acquire fourth absorbance data during the third rotation cycle, the fourth absorbance data being indicative of the absorbance within the blood sample in the sample analysis cavity of the cuvette.

[0083] In one or more example blood analyzers, the controller is configured to determine a fifth blood parameter, e.g., indicative of a second plasma-free hemoglobin level indicative of fragile blood cells in the blood sample, based on the fourth absorbance data.

[0084] In one or more example hematology analyzers, the photometer is configured to obtain initial absorbance data, first absorbance data, second absorbance data, third absorbance data, or fourth absorbance data by measuring absorbance using three or more wavelengths.

[0085] In one or more example blood analyzers, the controller is configured to control the photometer and any imaging device to measure initial absorbance data, first absorbance data, second absorbance data, third absorbance data, or fourth absorbance data, respectively, during multiple rotations of the rotatable member.

[0086] In one or more example blood analyzers, the controller is configured to integrate absorbance data acquired by the photometer during multiple rotations of the rotatable member.

[0087] A cuvette for blood analysis and suitable for use in the method and for a blood analyzer as defined herein is disclosed below: The cuvette comprises a sampling cavity with a fluid inlet for drawing up, e.g. obtaining, a blood sample, a sample analysis cavity for analyzing the blood sample, and a discharge cavity.

[0088] The discharge cavity is in fluid communication with the sampling cavity and the sample analysis cavity, such that the blood sample can flow from the sampling cavity to the sample analysis cavity via the discharge cavity. The sampling cavity and the sample analysis cavity are not in direct fluid communication with each other. Thus, in order for the blood sample to move from the sampling cavity to the sample analysis cavity, the blood sample must flow through the discharge cavity.

[0089] The cuvette is configured to transfer the blood sample from the sampling cavity to the sample analysis cavity through the discharge cavity when a force, such as a centrifugal force, is applied to the cuvette. In one or more example cuvettes, the cuvette has a first interface fluidly connecting the discharge cavity to the sampling cavity. The first interface can be configured to allow the blood sample to flow through the first interface when a centrifugal force that overcomes a third capillary force is applied to the cuvette. In one or more example cuvettes, the cuvette has a second interface fluidly connecting the discharge cavity to the sample analysis cavity. The second interface can be configured to allow the blood sample to flow from the discharge cavity to the sample analysis cavity through the second interface and can prevent flow from the sample analysis cavity to the discharge cavity. In one or more example cuvettes, the blood sample can automatically flow through the second interface, for example, because the first capillary force of the sample analysis cavity is greater than the second capillary force provided by the discharge cavity. In one or more example cuvettes, the cuvette lacks any means, such as a capillary channel and / or a siphon, configured to draw the blood sample away from the sample analysis cavity.

[0090] The blood sample introduced into the cuvette through the sampling cavity may be separated in the sample analysis cavity by further applying centrifugal force when the blood sample enters the sample analysis cavity. For example, red blood cells or disturbing elements may be separated and removed from the whole blood sample. In other words, the blood sample may be separated and analyzed in the same cavity, such as in the sample analysis cavity. As such, the sample analysis cavity may act as a centrifugal cavity. In other words, the cuvette may not include a centrifugal cavity for separating the blood sample in addition to the sample analysis cavity. In one or more example cuvettes, the sample analysis cavity is the innermost cavity of the cuvette. The separated body fluid is thereby located in the innermost cavity of the cuvette, which reduces the risk of the separated body fluid being contaminated by contact with the outside of the cuvette.

[0091] In one or more example cuvettes, the first interface and the second interface are disposed at an angle relative to each other. The first interface may be disposed along a first axis, such as along a longitudinal axis of the cuvette. The second interface may be disposed along a second axis, such as along a transverse axis of the cuvette. The first interface and the second interface may be disposed, for example, substantially perpendicular to each other. Substantially perpendicular may be understood herein as disposed at an angle within a range of 80-100 degrees relative to each other. However, other angles may be envisioned. The second interface may be disposed perpendicular to a longitudinal direction of the cuvette, such as perpendicular to a direction of a centrifugal force applied to the cuvette, in one or more example cuvettes. In other words, when the cuvette is placed in an analyzer and a centrifugal force is applied to the cuvette, the centrifugal force may act in a longitudinal direction of the cuvette.

[0092] The sample analysis cavity is configured to provide a first capillary force, which is greater than a second capillary force provided by the ejection cavity. The first capillary force may be achieved by the height and / or width of the sample analysis cavity, which is less than the capillary force achieved by the height and / or width of the ejection cavity. The height of the sample analysis cavity and the ejection cavity may be seen herein as the distance between the first and second inner surfaces of the respective cavities in the vertical direction of the cuvette, as defined in FIG. 4. By decreasing the distance between the inner surfaces of the cavities, the capillary force of the cavity may be increased. By configuring the sample analysis cavity to have a greater capillary force than the ejection cavity, i.e., the first capillary force is greater than the second capillary force, the transport of the blood sample from the ejection cavity to the sample analysis cavity may be increased, while the transport of fluid from the sample analysis cavity to the ejection cavity may be prevented. As such, the cuvette may be configured to prevent the blood sample from leaving the sample analysis cavity after the centrifugal force is removed, thereby ensuring that the entire volume of the blood sample remains in the sample analysis cavity after the centrifugal force is removed from the cuvette. The entire volume may be viewed herein as at least 90%, such as 95%, 96%, 97%, 98%, 99%, or 100% of the volume of blood acquired by the sampling cavity.

[0093] The discharge cavity has an opening to the exterior of the cuvette, which opening may be referred to herein as a discharge opening. The discharge opening may form an outlet through which air may be discharged from the sample analysis cavity to the exterior of the cuvette via the discharge cavity when the sample analysis cavity is filled with a blood sample. The cuvette may be configured to transfer air from the sampling cavity to the exterior of the cuvette via the discharge cavity and / or via the sampling cavity when blood is introduced into, e.g., drawn up by, the sampling cavity.

[0094] The discharge opening may be located at a first end of the cuvette in one or more example cuvettes. The discharge opening may cover the entire width of the discharge cavity, such that all sides of the discharge cavity may be open to the exterior of the cuvette.

[0095] In one or more example cuvettes, the discharge opening is an opening through an outer wall of the cuvette. The discharge opening can extend across a portion or the entire width of the discharge cavity. The opening allows air to escape from any cavity, such as the discharge cavity, the sampling cavity, and / or the sample analysis cavity, through the discharge cavity to the exterior of the cuvette when the cavity is filled with a blood sample. In one or more example cuvettes, the outlet of the discharge cavity to the exterior of the cuvette is located at a first end of the cuvette, such as at a first longitudinal end of the cuvette.

[0096] In one or more example cuvettes, the sampling cavity has an opening through the outer wall of the cuvette, which opening may be referred to herein as the sampling opening. The sampling opening may extend over a portion or the entire width of the sampling cavity. The sampling opening may allow air to escape from the sampling cavity as the sampling cavity draws up, e.g., fills with, the blood sample. In one or more example cuvettes, the sampling opening of the sampling cavity relative to the exterior of the cuvette is located at a first end of the cuvette. Thus, the sampling opening and the drain opening may be located at the same end of the cuvette.

[0097] In one or more example cuvettes, a drainage opening and / or a sampling opening that extends across the full width of each cavity can allow for the removal of shaping tools used during the manufacture of the cuvette, which can expedite the manufacture of the cuvette, which may reduce the time and cost to manufacture the cuvette.

[0098] The sampling cavity may be configured to provide a third capillary force. The third capillary force may be greater than the second capillary force in the discharge cavity. By configuring the cuvette such that the third capillary force is greater than the second capillary force, automatic transport of the blood sample from the sampling cavity may be prevented. Automatic transport herein means transport without applying an external force, such as a centrifugal force, to the cuvette. The greater capillary force in the sampling cavity may be achieved by the sampling cavity having a height that is less than the height of the discharge cavity. The height of the cavity may be seen herein as the distance between two parallel inner surfaces of the respective cavity. The third capillary force of the sampling cavity may be the same or different from the first capillary force, such as the capillary force of the sample analysis cavity. Since the cuvette is configured such that automatic transport of blood from the sampling cavity is prevented, the sampling cavity may be filled with the sample in several steps without acquiring excess fluid. Therefore, if the sampling cavity is not filled properly, more fluid can be drawn into the sampling cavity to fill it. Therefore, if it is noted that the inlet cavity is not completely filled with fluid, the cuvette can come into contact with the fluid to be sampled again, so that more fluid will be drawn into the inlet cavity by capillary action in the sampling cavity. Thus, a predefined sample volume corresponding to the volume of the sampling cavity can always be collected.

[0099] In one or more example cuvettes, the cuvette is comprised of a main body member, such as a unitary main body member, having an inner wall that defines a sampling cavity, a sample analysis cavity, and a discharge cavity within the body. A unitary body member herein means that the cuvette is made in one integral piece, for example, by molding or casting. By making the cuvette as a unitary piece, the cuvette does not include any joints / joints through which blood may leak out of the cuvette during centrifugation. This may reduce contamination of the outside of the cuvette and blood analyzer, which reduces the time required between analyses to clean and prepare the analyzer to receive another cuvette.

[0100] The sampling cavity, the sample analysis cavity, and the discharge cavity may be disposed within a main body member of the cuvette. The main body member of the cuvette may be made of a material having low absorbance for radiation at wavelengths used during analysis of the blood sample. In one or more example cuvettes, the material of the cuvette may be a plastic, such as polystyrene (PS), polymethylmethacrylate (PMMA), or polycarbonate (PC).

[0101] The centrifugal force applied to the cuvette can overcome a third capillary force that holds the blood sample in the sampling cavity, so that the blood sample can leave the sampling cavity via the discharge cavity and enter the sample analysis cavity. The sample analysis cavity can be positioned offset from the sampling cavity in the longitudinal direction of the cuvette, so that the centrifugal force can urge the blood sample toward and into the sample analysis cavity.

[0102] The cuvette may be configured to transfer air from the sample analysis cavity to the exterior of the cuvette via the exhaust cavity when a centrifugal force is applied to the cuvette. When a blood sample enters the sample analysis cavity, air within the sample analysis cavity may escape from the sample analysis cavity to the exterior of the cuvette via the second interface and the exhaust opening, thereby ensuring proper filling of the sample analysis cavity.

[0103] In one or more example cuvettes, the sampling cavity and the sample analysis cavity have equal volumes, such as substantially equal volumes, such that a predefined volume of a blood sample can be obtained by the sampling cavity and the same volume of fluid can be analyzed in the sample analysis cavity.

[0104] The volume of the sampling cavity can be in the range of 10-100 microliters (μL) or 20-60 microliters (μL), such as in the range of 30-50 μL, such as in the range of 30-40 μL, such as in the range of 30-35 μL, such as 32 μL. The volume of the sample analysis cavity can be in the range of 10-100 microliters (μL) or 20-60 microliters (μL), such as in the range of 30-50 μL, such as in the range of 30-40 μL, such as in the range of 30-35 μL, such as 32 μL.

[0105] In one or more example cuvettes, the sample analysis cavity has a substantially uniform elongated shape extending in a first direction between a first end and an opposing second end of the cuvette. The first end and the second end of the cuvette may be disposed at opposing longitudinal ends of the cuvette. The first direction may be parallel to an intended direction of centrifugal force applied to the cuvette, such as a direction of centrifugal force applied to the cuvette when the cuvette is analyzed using a hematology analyzer configured to receive the cuvette.

[0106] In one or more example cuvettes, the overall length of the cuvette, such as the longitudinal extension of the cuvette defined in Figure 4, may be in the range of 30 to 50 mm or 36 to 44 mm, such as in the range of 38 to 42 mm, such as in the range of 39 to 40 mm. The overall length may be measured from the tip of a first longitudinal end of the cuvette to a second longitudinal end of the cuvette.

[0107] In one or more example cuvettes, the overall width of the cuvette, such as the lateral extension of the cuvette as defined in Figure 4, can be in the range of 15 to 28 mm or 18 to 24 mm, such as in the range of 19 to 23 mm, such as in the range of 20 to 22 mm. In one or more example methods, the width of the cuvette can be 21 mm.

[0108] In one or more example cuvettes, the overall width of the cuvette, such as the vertical extension of the cuvette defined in FIG. 4, can be in the range of 1.9 to 2.4 mm, such as in the range of 2.0 to 2.3 mm, such as in the range of 2.1 to 2.2 mm.

[0109] In one or more example cuvettes, the sample analysis cavity can have a length, such as the longitudinal extension of the cuvette defined in FIG. 4, within the range of 10 to 20 mm, e.g., 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, or 20 mm, and / or any range limited by the dimensions discussed in this paragraph.

[0110] In one or more example cuvettes, the sample analysis cavity can have a width, such as the lateral extension of the cuvette defined in FIG. 4, of 2 to 7 mm, e.g., 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, or 7 mm, and / or any range limited by the dimensions discussed in this paragraph.

[0111] In one or more example cuvettes, the sample analysis cavity can have a height in the range of 0.2-0.7 mm, e.g., 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, or 0.7 mm, and / or any range limited by the dimensions discussed in this paragraph, such as the vertical extension of the cuvette defined in Figure 4. In one or more example cuvettes, the height of the sample analysis cavity can be 0.5 mm, e.g., 500 μm.

[0112] In one or more example cuvettes, the sampling cavity can have a length, such as an average length, within the range of 5 to 15 mm, e.g., 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, or 15 mm, and / or any range limited by the dimensions discussed in this paragraph.

[0113] In one or more example cuvettes, the sampling cavity can have a width, such as an average width, within the range of 5 to 15 mm, e.g., 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, or 15 mm, and / or any range bounded by the dimensions discussed in this paragraph.

[0114] In one or more example cuvettes, the sampling cavity can have a height in the range of 0.2-0.7 mm, e.g., 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, or 0.7 mm, and / or any range limited by the dimensions discussed in this paragraph, such as the vertical extension of the cuvette defined in Figure 4. In one or more example cuvettes, the height of the sampling cavity can be in the range of 500-650 μm, e.g., 575 μm.

[0115] In one or more example cuvettes, the ejection cavity can have a length within the range of 5 to 10 mm, e.g., 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm, and / or any range limited by the dimensions discussed in this paragraph.

[0116] In one or more example cuvettes, the ejection cavity can have a width within the range of 3 to 8 mm, e.g., 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, or 8 mm, and / or within any range bounded by the dimensions discussed in this paragraph.

[0117] In one or more example cuvettes, the ejection cavity can have a height in the range of 0.4 to 2 mm, e.g., 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, or 2.0 mm, and / or any range limited by the dimensions discussed in this paragraph, such as the vertical extension of the cuvette as defined in Figure 4. In one or more example cuvettes, the height of the ejection cavity can be 1 mm, e.g., 1000 μm.

[0118] In one or more example cuvettes, the body member includes a tip. The sampling cavity may be located at the tip of the body member, such that the inlet of the sampling cavity is located at the tip of the cuvette. By locating the inlet at the tip of the cuvette, filling of the sampling cavity with the blood sample may be facilitated because the tip allows for precise positioning of the inlet of the sampling cavity in the blood sample being drawn up.

[0119] In one or more example cuvettes, the sampling cavity, such as the inner surface of the sampling cavity, is configured to slope toward the sample analysis cavity. By providing a slope to the sample analysis cavity, transport of the blood sample from the sampling cavity to the sample analysis cavity can be improved. The sampling cavity can be configured to slope outwardly toward the opening to further facilitate removal of the shaping tool after shaping of the cuvette.

[0120] In one or more example cuvettes, the cuvette, such as the sample analysis cavity of the cuvette, is reagent-free. When the cuvette is reagent-free, analysis of the blood sample, such as a blood sample, can be performed by directly measuring hemoglobin (Hb) derivatives contained in the body. In the case of blood, the hemoglobin derivatives can be, for example, reduced hemoglobin (Hb), such as deoxyhemoglobin (reduced form), oxyhemoglobin (HbO2), methemoglobin (met-Hb), carboxyhemoglobin (HbCO), or other types of hemoglobin. Making the cuvette reagent-free reduces the cost of manufacturing the cuvette and also reduces the time it takes to manufacture the cuvette.

[0121] In one or more example cuvettes, the walls of the sampling cavity are coated with a wetting agent, which can aid in wicking the blood sample into the sampling cavity.

[0122] In one or more example cuvettes, the sample analysis cavity can include a reagent configured to react with the blood sample. The reagent can be disposed on an inner surface of the sample analysis cavity such that it contacts the blood sample as it enters the sample analysis cavity. The reagent can be applied to the sample analysis cavity during manufacture of the cuvette. Different reagents can be provided within the cavity depending on the analysis to be performed, thereby allowing the cuvette to be adapted for analysis of different biological parameters of blood. The reagent can react different hemoglobin derivatives to become the same derivative, thereby reducing interference at different wavelengths, which can facilitate the analysis procedure of the blood sample.

[0123] In one or more example cuvettes, the cuvettes may include a unique identifier to identify each respective cuvette. The unique identifier may be a visual identifier, such as a barcode or QR code, or a digital identifier, such as a Radio Frequency Identification (RFID) tag. The unique identifier may be used to identify the cuvette used for a particular blood sample and / or analysis. In one or more example cuvettes, the identifier may be identified by a hematology analyzer, and measurements from the hematology analyzer may be automatically stored with the cuvette's unique identifier.

[0124] The cuvettes can be disposable or can be single-use, eg, cuvettes configured for single use, that is used once for an analysis and then discarded.

[0125] The cuvettes may be manufactured by conventional means, for example as disclosed in WO 2007 / 008137.

[0126] In the following, the disclosed method for analyzing a blood sample, the analyzer for analyzing a blood sample, and the cuvette for analyzing a blood sample will be described in further detail with reference to the figures. The figures are schematic in nature and simplified for clarity, and merely show details that are helpful in understanding the present disclosure, while other details are omitted. The same reference numerals are used throughout for identical or corresponding parts.

[0127] 1 shows a method 100 for analyzing a blood sample. The method may be performed using a blood analyzer, which may be seen herein as an analytical device for analyzing blood.

[0128] The method includes disposing S102 a cuvette on the rotatable member, the cuvette comprising a sampling cavity and a sample analysis cavity. The sampling cavity contains the blood sample to be analyzed.

[0129] In one or more example methods, the method may include rotating the rotatable member at an initial speed in an initial rotation cycle that is insufficient for the transfer of the blood sample from the sampling cavity to the sample analysis cavity S104. The initial speed may create an initial centrifugal force acting on the blood sample during the initial rotation cycle, the initial centrifugal force being less than the capillary force acting on the blood sample in the sampling cavity. In other words, the initial speed may be insufficient for the transfer of the blood sample from the sampling cavity to the sample analysis cavity. Thereby, the blood sample will be retained in the sampling cavity during the initial rotation cycle. As such, the sample analysis cavity will remain empty, where empty means no blood, which allows an initial measurement to be performed on the empty sample analysis cavity of the cuvette to detect any contamination or damage to the cuvette that may affect the analysis results of the blood sample. In one or more example methods, the initial rotation cycle is performed before the first rotation cycle.

[0130] In one or more example methods, the method may include obtaining S106 initial absorbance data indicative of absorbance in or through a sample analysis cavity of the cuvette using a photometer and during an initial rotation cycle. Because a blood sample is held in the sampling cavity during the initial rotation cycle, the initial absorbance data may be absorbance data indicative of absorbance through a blank sample.

[0131] In one or more example methods, the method may include determining S108 cuvette parameters based on the initial absorbance data. The cuvette parameters may be, e.g., may indicate, a contamination level associated with the cuvette, an absorbance data of an empty cuvette, and the presence of a cuvette in the receptacle of the rotatable member. The contamination level associated with the cuvette may include scratches on the surface of the cuvette, discoloration of the cuvette, contamination of the cuvette, and / or any other imperfections of the cuvette in the area of ​​the sample analysis cavity of the cuvette. Contamination may be caused by, for example, fingerprints applied to the area of ​​the sample analysis cavity due to incorrect handling of the cuvette by an operator.

[0132] In one or more example methods, the method may include providing an output S109 indicative of the cuvette parameters. In one or more example methods, providing an output S109 may include displaying a message to an operator indicative of the cuvette parameters S109A. The message may indicate, for example, that a contamination level of the cuvette is equal to or greater than a predetermined contamination threshold, or that a contamination level is less than a predetermined contamination threshold. A contamination level equal to or greater than a contamination threshold may indicate to an operator that analysis of the blood sample using the cuvette cannot be performed. A contamination level less than a contamination threshold may indicate to an operator that the operator may proceed with analysis of the blood sample using the cuvette.

[0133] In one or more example methods, providing an output S109 can include providing the cuvette parameters to a compensation function S109B, which can compensate for contamination levels and / or absorbance data of an empty cuvette during subsequent measurement and determination of blood parameters using the cuvette.

[0134] The method includes rotating S110 the rotatable member at a first speed in a first rotation cycle for transfer of the blood sample from the sampling cavity to the sample analysis cavity. The first speed can be configured to create a first centrifugal force greater than a third capillary force generated by the sampling cavity of the cuvette. The first centrifugal force transfers the blood sample from the sampling cavity to the sample analysis cavity. In one or more example methods, the first rotation cycle is performed after the initial rotation cycle.

[0135] In one or more example methods, the method may include acquiring S112 first absorbance data indicative of absorbance in the blood sample in the sample analysis cavity of the cuvette using the photometer and during the first rotation cycle.

[0136] In one or more example methods, the method may include determining S113 a fill parameter indicative of a blood level, such as indicative of a fill level, such as indicative of an amount of blood, in the sample analysis cavity of the cuvette based on the first absorbance data. The fill parameter may in one or more example methods indicate one or more of the following: the sample analysis cavity is underfilled, the sample analysis cavity is improperly filled, and the sample analysis cavity is correctly filled. In one or more example methods, the sample analysis cavity may be determined to be underfilled when the first absorbance data is less than a first blood level threshold. Too low a blood level, such as an underfilled cuvette, may cause the absorbance data to be lower than when the sample analysis cavity is correctly filled. A sample analysis cavity being improperly filled may be viewed herein as not being filled with blood, such as being filled with a fluid other than blood.

[0137] In one or more example methods, the method may include providing an output S113A indicative of the fill parameter, such as indicative of an amount of blood in a sample analysis cavity of the cuvette. In one or more example methods, the output may indicate that further analysis of the blood sample is not possible, such as when the fill parameter indicates that the cuvette is underfilled and / or improperly filled. In one or more example methods, the output may indicate that further analysis of the blood sample is possible, such as when the fill parameter indicates that the cuvette is properly filled. In one or more example methods, the output may be a signal that prevents further analysis of the blood sample, such as when the fill parameter indicates that the cuvette is underfilled and / or improperly filled. In one or more example methods, the output may be a signal that allows further analysis of the blood sample, such as when the fill parameter indicates that the cuvette is properly filled.

[0138] In one or more example methods, the method can include determining S114 a first blood parameter that is, for example, indicative of, a total hemoglobin level of the blood sample based on the first absorbance data.

[0139] The method includes rotating the rotatable member S116 at a second speed in a second rotation cycle to separate blood portions from plasma within the blood sample. The second rotation cycle may be performed after the first rotation cycle.

[0140] The method includes obtaining second absorbance data S118 using the photometer during or after the second rotation cycle, The second absorbance data is indicative of absorbance within the plasma.

[0141] The method includes determining S119 a second blood parameter based on the second absorbance data. The second blood parameter is, for example, indicative of, a plasma-free hemoglobin level of the blood sample.

[0142] The method includes providing an output S120 indicative of the second blood parameter.

[0143] In one or more example methods, the method may include obtaining S121, using a photometer, third absorbance data during the second rotation cycle, the third absorbance data indicative of a separation time of red blood cells from plasma.

[0144] In one or more example methods, the method can include determining S122 a third blood parameter based on the third absorbance data and the first absorbance data. The third blood parameter is, e.g., indicative of, an erythrocyte sedimentation rate of the blood sample.

[0145] In one or more example methods, the method includes S123 providing an output indicative of the third blood parameter.

[0146] In one or more example methods, the method may include acquiring S124, using an imaging device, first image data indicative of an image of at least a portion of the blood sample in the sample analysis cavity after the second rotation cycle.

[0147] In one or more example methods, the method can include determining S126 a fourth blood parameter that is, for example, indicative of, a hematocrit level of the blood sample based on the first image data.

[0148] In one or more example methods, the method can include providing an output indicative of the fourth blood parameter S128.

[0149] In one or more example methods, the method may include rotating the rotatable member at a third speed in a third rotation cycle after the second rotation cycle S130. In one or more example methods, the third speed is faster than the first speed, the second speed, and the initial speed. In one or more example methods, the third speed may be equal to the second speed. In one or more example methods, the third rotation cycle may be longer than the second rotation cycle to induce hemolysis in the blood sample. In other words, hemolysis may be induced on the blood sample during the third rotation cycle by centrifuging the blood sample at a faster speed or for a longer time than the second rotation cycle.

[0150] In one or more example methods, the method may include acquiring S132 fourth absorbance data indicative of absorbance within the blood sample in the sample analysis cavity of the cuvette using the photometer and during the third rotation cycle.

[0151] In one or more example methods, the method can include determining a fifth blood parameter S134 based on the fourth absorbance data. The fifth blood parameter can be a second plasma-free hemoglobin level indicative of fragile blood cells in the blood sample. By comparing the second plasma-free hemoglobin level to the first plasma-free hemoglobin level, a level of fragile blood cells in the blood sample can be determined.

[0152] In one or more example methods, the method may include S136 providing an output indicative of the fifth blood parameter, such as displaying information indicative of the fifth blood parameter.

[0153] 2 shows a schematic diagram of an example blood analyzer 100 according to the present disclosure. Blood analyzer 100 can include a housing 110 that can house any and / or all of the parts of blood analyzer 100 discussed herein, such as rotatable members, a photometer, a controller, a display, and / or a drive unit.

[0154] The blood analyzer 100 comprises a rotatable member 200. The rotatable member 200 is rotatably disposed within the housing 110. The rotatable member 200 may be rotatably disposed about a rotation axis 202. The rotatable member comprises a receptacle 204 for receiving a cuvette. The cuvette comprises a sampling cavity and a sample analysis cavity. When the cuvette is placed on the rotatable member, the sampling cavity of the cuvette is intended to contain a blood sample to be analyzed, while the sample analysis cavity is intended to be empty. Empty in this specification means that the sample analysis cavity does not contain a blood sample, but may contain air. The rotatable member 200 may be a circular member, such as a disk. The receptacle 204 may comprise a measuring eye 206, such as an aperture, to allow light to pass through the rotatable member 200. The measuring eye 206 may be positioned in the receptacle 204 such that when the cuvette is placed in the receptacle 204, the measuring eye 206 overlaps with a sample analysis cavity of the cuvette in at least a first angular position of the rotatable member 200. The measuring eye 206 may be positioned on the rotatable member 200 at a distance r from the axis of rotation 202. The blood analyzer 100 may include a drive unit 208, such as an electric motor, for driving, e.g., rotating, the rotatable member 200.

[0155] The blood analyzer 100 includes a photometer 300. The photometer 300 is configured to obtain, e.g., measure, absorbance data associated with a blood sample in a sample analysis cavity and / or a cuvette. The photometer 300 can be a multi-wavelength photometer. The photometer 300 can include a light source 302 for emitting light at respective wavelengths and an optical sensor 304, such as a photodiode, for measuring how much light is absorbed by an object located between the light source 302 and the optical sensor 304.

[0156] The blood analyzer 100 can include a display 500 configured to visually provide information to an operator of the blood analyzer 100, such as to visually display information indicative of the cuvette parameter, the first blood parameter, the second blood parameter, the third blood parameter, the fourth blood parameter, and / or the fifth blood parameter.

[0157] The blood analyzer 100 can include a display 500 for displaying, eg, visually presenting, information to an operator of the blood analyzer 100 .

[0158] The blood analyzer 400 can include an imaging device 306, such as a camera, for taking images relating to the blood sample in the sample analysis cavity and / or cuvette.

[0159] The blood analyzer can include a controller 400. The controller 400 can be configured to control the photometer 300, the imaging device 306, the rotatable member 200, the drive unit 208, and / or the display 500. The controller 400 can be configured to perform any one of the operations disclosed in Figures la-ld (such as any one or more of S102, S104, S106, S108, S110, S112, S114, S116, S118, S119, S120, S121, S122, S123, S124, S126, S128, S130, S132, S134).

[0160] The controller 400 may be configured to control the drive unit 208 to control the speed of the rotatable member 200 .

[0161] The controller 400 may be configured to rotate the rotatable member 200 at a first speed in a first rotation cycle to transfer the blood sample from the sampling cavity to the sample analysis cavity.

[0162] The controller 400 may be configured to rotate the rotatable member 200 at a second speed in a second rotation cycle after the first rotation cycle to separate blood portions from plasma within the blood sample.

[0163] The controller 400 can be configured to control the photometer 300 to obtain second absorbance data indicative of the absorbance within the plasma of the separated blood sample during a second rotation cycle.

[0164] The controller 400 may be configured to determine a second blood parameter that is, for example, indicative of, the plasma-free hemoglobin level of the blood sample based on the second absorbance data.

[0165] The controller 400 may be configured to provide an output indicative of the second blood parameter, such as to a display 500.

[0166] The controller 400 may be configured to rotate the rotatable member 200 at an initial speed in an initial rotation cycle prior to the first rotation cycle, the initial speed being insufficient for transfer of the blood sample from the sampling cavity to the sample analysis cavity.

[0167] The controller 400 may be configured to control the photometer 300 to acquire initial absorbance data indicative of the absorbance within the sample analysis cavity of the cuvette during an initial spin cycle.

[0168] The controller 400 can be configured to determine a cuvette parameter that is, for example, indicative of a contamination level associated with the cuvette based on the initial absorbance data.

[0169] The controller 400 may be configured to provide an output indicative of the cuvette parameters, such as to a display 500.

[0170] The controller 400 may be configured to control the photometer 300 to obtain, during a first rotation cycle, first absorbance data indicative of the absorbance in the blood sample in the sample analysis cavity of the cuvette.

[0171] The controller 400 may be configured to determine a first blood parameter that is, for example, indicative of, a total hemoglobin level of the blood sample based on the first absorbance data.

[0172] The controller 400 may be configured to provide an output indicative of the first blood parameter, such as to a display 500.

[0173] The controller 400 may be configured to control the photometer 300 to obtain third absorbance data during the second rotation cycle, the third absorbance data being indicative of the separation time of red blood cells from the plasma in the sample analysis cavity of the cuvette.

[0174] The controller 400 may be configured to determine a third blood parameter, for example indicative of, the erythrocyte sedimentation rate of the blood sample in the sample analysis cavity of the cuvette based on the third absorbance data and the first absorbance data.

[0175] The controller 400 may be configured to provide an output indicative of the third blood parameter, such as to a display 500.

[0176] The controller 400 may be configured to control the imaging device 306 to acquire, after the second rotation cycle, first image data indicative of an image of at least a portion of the blood sample within the sample analysis cavity of the cuvette.

[0177] The controller 400 may be configured to determine a fourth blood parameter that is, for example, indicative of, a hematocrit level of the blood sample based on the first image data.

[0178] The controller 400 may be configured to provide an output indicative of the fourth blood parameter, such as to a display.

[0179] The controller 400 may be configured to rotate the rotatable member 200 at a third speed in a third rotation cycle after the second rotation cycle, the third speed being faster than the first speed, the second speed, and the initial speed.

[0180] The controller 400 may be configured to control the photometer 300 to obtain, during a third rotation cycle, fourth absorbance data indicative of the absorbance within the blood sample in the sample analysis cavity of the cuvette.

[0181] The controller 400 may be configured to determine a fifth blood parameter, for example indicative of a second plasma-free hemoglobin level indicative of fragile blood cells in the blood sample, based on the fourth absorbance data.

[0182] The controller 400 may be configured to control the photometer and any imaging device to measure initial absorbance data, first absorbance data, second absorbance data, third absorbance data, image data, or fourth absorbance data, respectively, during multiple rotations of the rotatable member 200.

[0183] The controller 400 may be configured to integrate the absorbance data acquired by the photometer 300 during multiple rotations of the rotatable member 200 .

[0184] 3 shows a schematic diagram of an example photometer 300 according to the present disclosure. The photometer 300 can include multiple light sources 302, such as light sources 302A, 302B, 302C, and multiple optical sensors 304, such as optical sensors 304A, 304B, 304C. The light sources 302A, 302B, 302C and corresponding optical sensors 304A, 304B, 304C can be disposed on opposite sides of the rotatable member 200, such that light emitted from each light source 302A, 302B, 302C passes through a measuring eye 202 in the rotatable member 200 and a cuvette disposed in a receptacle 204 of the rotatable member 200 before reaching the corresponding optical sensor 304A, 304B, 304C. In other words, the multiple light sources 302A, 302B, 302C may be disposed on a first side of the rotatable member 200, and the one or more optical sensors 304A, 304B, 304C may be disposed on a second side of the rotatable member 200. The first side of the rotatable member 200 and the second side of the rotatable member 200 may be opposing sides of the rotatable member. In one or more example blood analyzers, the light sources 302A, 302B, 302C may be LEDs. Each light source 302A, 302B, 302C may be configured to emit a different wavelength of light. The photometer 300 may be configured to obtain initial absorbance data, first absorbance data, second absorbance data, third absorbance data, and / or fourth absorbance data by measuring absorbance using three or more wavelengths.

[0185] FIG. 4 shows a perspective view of a cuvette 1 according to one or more examples of the present disclosure. The cuvette 1 comprises a sampling cavity 2, a discharge cavity 3, and a sample analysis cavity 4. Throughout this document, the cuvette will be described with reference to the coordinate system disclosed in FIG. 4, where the X-axis defines a vertical direction spanning the length of the cuvette 1 (e.g., between a first vertical end 6 and a second vertical end 7 of the cuvette 1), the Y-axis defines a horizontal direction spanning the width of the cuvette 1, and the Z-axis defines a vertical direction spanning the height of the cuvette 1. The main plane of the cuvette 1 discussed herein is a plane extending in the vertical and horizontal directions of the cuvette 1. A plane perpendicular to the main plane may be one or more of a plane extending in the vertical and vertical directions of the cuvette 1 and a plane extending in the horizontal and vertical directions of the cuvette 1. The cuvette 1 may have a longer extension in the vertical and horizontal directions compared to the vertical direction, and may therefore be referred to as having a flat shape or being a flat cuvette.

[0186] FIG. 5 illustrates a cuvette 1 according to one or more examples of the present disclosure. The cuvette 1 includes a sampling cavity 2, a sample analysis cavity 4, and a discharge cavity 3. The sampling cavity 2 includes a fluid inlet 22 for collecting a blood sample. The cuvette 1 has a main body member 10 including a base portion 11. The base portion 11 can be solid and can be configured to be touched by an operator during handling of the cuvette without causing interference with the results of the analysis of the blood. In a cuvette according to one or more examples, the base portion 11 of the main body member 10 can have a different surface texture than the main body member 10 in the area of ​​the sampling cavity 2 and / or the sample analysis cavity 4. Providing a base portion 11 with a different surface texture can provide an operator of the cuvette with a visual indication of the areas that can be touched without interfering with the results of the analysis. The main body member 10 can include a mounting element 5 that can be configured to fit a cuvette holder into an analysis device. The mounting elements 5 may be arranged so that the cuvette 1 can only be positioned in one way within the analytical device. In the example cuvette 1 shown in FIG. 5, the mounting elements 5 may be shaped as recesses in the main body member 10 of the cuvette 1.

[0187] The sampling cavity 2, the sample analysis cavity 4, and the discharge cavity 3 may be disposed within, e.g., formed within, a main body member 10 of the cuvette 1. The cuvette 1 may consist of a unitary main body member 10, such as an integral part, having an inner wall that defines the sampling cavity 2, the sample analysis cavity 4, and the discharge cavity 3 within the main body member 10. The main body member 10 of the cuvette 1 may be made of a material that has low absorbance for radiation at wavelengths used during analysis of blood samples. The main body member 10 may be made of a plastic, such as polystyrene (PS), polymethyl methacrylate (PMMA), or polycarbonate (PC).

[0188] The discharge cavity 3 is in fluid communication with the sampling cavity 2 and the sample analysis cavity 4, such that blood can flow from the sampling cavity 2 to the sample analysis cavity 4 via the discharge cavity 3. The discharge cavity 3 can be fluidly connected with the sampling cavity 2 via a first interface 23. The first interface 23 can be disposed along the longitudinal axis of the cuvette 1. The discharge cavity 3 can be fluidly connected with the sample analysis cavity 4 via a second interface 34. The second interface 34 can be disposed along the transverse axis of the cuvette 1. The sampling cavity 2 and the sample analysis cavity 4 are not in direct fluid communication with each other. Thus, for the blood sample to move from the sampling cavity 2 to the sample analysis cavity 4, the blood sample must flow through the discharge cavity 3, such as via the first interface 23 and the second interface 34.

[0189] The sample analysis cavity 4 is configured to provide a first capillary force, the first capillary force being greater than a second capillary force provided by the discharge cavity 3. This may be achieved by the height of the sample analysis cavity 4 being less than the height of the discharge cavity 3. The second interface 34 may be configured to allow the blood sample to flow from the discharge cavity to the sample analysis cavity through the second interface 34, and to prevent flow of the blood sample from the sample analysis cavity 4 to the discharge cavity 3. This ensures that the entire volume of the blood sample enters and remains within the sample analysis cavity 4.

[0190] The first interface 23 and the second interface 34 may be disposed at an angle a relative to one another. The first interface 23 and the second interface 34 may, for example, be disposed substantially perpendicular to one another.

[0191] The sampling cavity 2 is configured to provide a third capillary force, the third capillary force being greater than the second capillary force. The third capillary force, which is greater than the second capillary force, prevents automatic transport of the blood sample from the sampling cavity 2 to the discharge cavity 3. This may be achieved by the height of the sampling cavity 2 being less than the height of the discharge cavity 3. The third capillary force may be the same as or different from the first capillary force. The first interface 23 may be configured to allow the blood sample to flow through the first interface 23 when a centrifugal force is applied to the cuvette 1 that overcomes the third capillary force. As such, the cuvette 1 may be configured to transport the blood sample from the sampling cavity 2 through the discharge cavity 3 to the sample analysis cavity 4 when a centrifugal force is applied to the cuvette 1.

[0192] The blood sample introduced into the cuvette 1 via the sampling cavity 2 may be separated in the sample analysis cavity 4 by applying further centrifugal force as the blood sample enters the sample analysis cavity 4 .

[0193] The discharge cavity 3 has an outlet 31 to the exterior of the cuvette 1. The outlet 31 of the discharge cavity 3 may be located at a first end 6, such as a first longitudinal end, of the cuvette 1. The outlet 31 may be an opening through a first outer wall of the first end 6 of the cuvette 1, said opening extending across the entire width of the discharge cavity 3. Thereby, all sides of the discharge cavity 3 may be open to the exterior of the cuvette 1. The outlet 31 is configured to allow air to be discharged from the sample analysis cavity 4 through the discharge cavity 3 to the exterior of the cuvette 1 when the sample analysis cavity 4 is filled with a blood sample. The outlet 31 covering the entire width of the discharge cavity 3 also allows the shaping tool to be removed from the main body member 10 after the manufacture of the cuvette 1.

[0194] The sampling cavity 2 has an opening 21 through a first outer wall of the first end 6 of the cuvette 1. The opening 21 extends across the entire width of the sampling cavity 2. The opening 21 of the sampling cavity 2 can allow air to escape from the sampling cavity when the sampling cavity 2 is filled, e.g., drawing up a blood sample. The opening 21 can further allow for removal of a shaping tool used during the manufacture of the cuvette 1. The opening 21 of the sampling cavity 2 can be located at the same end of the cuvette 1 as the outlet 31. The main body member 10 can include a tip 12. The tip 12 can be located at the first end 6. A sidewall of the first end 6 can include a bend that forms the tip 12. The sampling cavity 2 can be located at the tip 12 of the main body member 10, such that the inlet 22 of the sampling cavity 2 is located at the tip 12 of the cuvette 1. By locating the inlet 22 at the tip 12 of the cuvette 1, filling of the sampling cavity with the blood sample can be facilitated because the tip 12 allows for precise positioning of the inlet 22 in the blood sample to be drawn up. When the tip 12 is immersed in the blood sample, the capillary forces of the sampling cavity 2 will draw the blood into the sampling cavity 2 through the inlet 22. The inlet 22 can be a section of the opening 21 located at the tip 2 of the cuvette 1. The sampling cavity 2, such as the inner surface 24 of the sampling cavity 2, can be configured to slope towards the sample analysis cavity 4. By providing the sampling cavity 2 with a sloped inner surface 24, the transport of the blood sample from the sampling cavity 2 to the sample analysis cavity 4 can be improved. The sampling cavity 2, such as the inner surface 24, can be configured to slope outwardly towards the opening 21. Thereby, removal of the shaping tool after shaping of the cuvette 1 can be facilitated.

[0195] The sample analysis cavity 4 may have a substantially uniform elongated shape extending in a first direction from a first end 6 of the cuvette 1 to / to an opposing second end 7 of the cuvette 1. The first end 6 and second end 7 of the cuvette may be disposed at opposing longitudinal ends of the cuvette 1. The first direction may be parallel to an intended direction of centrifugal force applied to the cuvette, such as a direction of centrifugal force applied to the cuvette when the cuvette 1 is analyzed using an analytical device configured to receive the cuvette 1.

[0196] In one or more example cuvettes, the sample analysis cavity 4 can be offset from the sampling cavity 2 in a longitudinal direction of the cuvette 1. In one or more example cuvettes, the sample analysis cavity 4 can be offset from the sampling cavity 2 in a transverse direction of the cuvette 1. In one or more example cuvettes, the sample analysis cavity 4 can be offset from the sampling cavity 2 in a longitudinal direction of the cuvette 1 and in a transverse direction of the cuvette 1.

[0197] FIG. 6 shows the location of the first cutting plane AA, the second cutting plane BB, the third cutting plane CC, and the fourth cutting plane DD, which are used for the cross-sectional views of FIGS. 7-10. The cutting plane AA extends in the longitudinal direction of the cuvette through the sampling cavity 2. The cross-sectional view of the cutting plane AA is further described with reference to FIGS. 7A and 7B. The cutting plane BB extends in the longitudinal direction of the cuvette through the discharge cavity 3 and the sample analysis cavity 4. The cross-sectional view of the cutting plane AA is further described with reference to FIGS. 8A and 8B. The cutting plane CC extends in the transverse direction of the cuvette 1 through the discharge cavity 3 and the sampling cavity 2. The cross-sectional view of the cutting plane CC is further described with reference to FIG. 9. The cutting plane DD extends in the transverse direction of the cuvette 1 through the sample analysis cavity 4. The cross-sectional view of the cutting plane DD is further described with reference to FIG. 10.

[0198] Figure 7A shows a cutaway view and Figure 7B shows a cross-sectional view of the cuvette 1 through section plane AA. As can be seen in the cutaway view of Figure 7A, the sampling cavity 2 is disposed at a first end 6 of the cuvette 1 within the main body 11. The sampling cavity 2 has an opening 21 at the first end 6 through the outer wall of the cuvette 1.

[0199] 7B shows a cross-section of the cuvette looking towards the tip 12 of the cuvette 1. As can be seen, the opening 21 of the sampling cavity 2 extends across the entire width of the sampling cavity 2 to an inlet 22 located at the tip 12.

[0200] FIG. 8A shows a cutaway view, and FIG. 8B shows a cross-sectional view of the cuvette 1 through the cut plane BB. The discharge cavity 3 is disposed at the first end 6 of the cuvette 1 and extends between the first end 6 and the sample analysis cavity 4. The sample analysis cavity 4 extends longitudinally from the discharge cavity 3 towards the second end 7 of the cuvette 1. As can be seen in the cutaway view of FIG. 8A, the sample analysis cavity 4 is narrower than the discharge cavity 3, e.g. has a lower height than the discharge cavity 3. Because the sample analysis cavity 4 has a lower height than the discharge cavity 3, the first capillary force is greater than the second capillary force. Thereby, the transport of the blood sample from the discharge cavity 3 through the second interface 34 to the sample analysis cavity 4 can be increased, because the first capillary force draws the blood sample into the sample analysis cavity 4. The first capillary force being greater than the second capillary force further prevents fluid from flowing from the sample analysis cavity 4 back to the exhaust cavity 3 .

[0201] The cross-sectional view in FIG. 8B shows a cross-section of the cuvette as seen towards the tip 12 of the cuvette 1. As can be seen, the opening 21 of the sampling cavity 2 and the outlet 31 of the discharge cavity 3 are connected such that the first outer wall of the cuvette at the first end 6 is open over the entire length of the sampling cavity 2 and the discharge cavity 3. This allows a shaping tool with a common shaping core for all cavities to be removed through the opening 21 and the outlet 31. The first interface 23 is located in the longitudinal direction of the cuvette and separates the sampling cavity 2 from the discharge cavity 3. As can be seen in FIG. 5B, the height of the opening of the first interface 31 is lower than the height of the sample analysis cavity 4 and the sampling cavity 2.

[0202] FIG. 9 shows a cross-sectional view of the cuvette 1 through the cutting plane CC. As discussed above, the height of the sampling cavity 3 is lower than the height of the discharge cavity 3. Because the sampling cavity 2 has a lower height than the discharge cavity, the third capillary force in the sampling cavity 2 is greater than the second capillary force. Thereby, the blood sample in the sampling cavity can be prevented from automatically flowing from the sampling cavity 2 to the discharge cavity 3. The sampling cavity 2 and the discharge cavity 3 can be connected by a first interface 23. The height of the first interface 23 can have a lower height than both the sampling cavity 2 and the discharge cavity 3. Therefore, the first interface 23 can be an area adjacent to the sampling cavity 2 having a very narrow thickness to further ensure that there is no capillary transport from the sampling cavity 2 to the discharge cavity 3. Therefore, the first interface can act as a lock that prevents the blood sample from flowing from the sampling cavity 2 to the discharge cavity 3. A centrifugal force can be applied to the cuvette 1 to transport the blood sample to the discharge cavity 3. When the centrifugal force applied to the cuvette 1 overcomes the third capillary force, the blood sample can leave the sampling cavity 2 via the first interface 23 and enter the discharge cavity 3, from where the blood sample can enter the sample analysis cavity 4.

[0203] 10 shows a cross-sectional view of the cuvette 1 through the cut plane DD. As can be seen in FIG. 10, comparing that cross-sectional view with cross-sectional view CC of FIG. 9, the cross-sectional area of ​​the sample analysis cavity 3, such as the height and width of the sample analysis cavity 3, is smaller than the cross-sectional area of ​​the discharge cavity 3, thereby causing the sampling cavity 4 to have a greater capillary force than the discharge cavity 3. Furthermore, the lower height and narrower width of the sample analysis cavity 4 compared to the height and width of the discharge cavity 3 allows the portion of the shaping tool furthest within the main body member 11 of the cuvette 1 during manufacture, such as the portion that molds the sample analysis cavity 4, to be removed through the wider outer section of the cuvette 1, such as through the wider discharge cavity 3.

[0204] It should be noted that the features described in the embodiments illustrated in Figures 4-10 are not limited to these particular embodiments, and thus any features of the cuvettes and components included therein and described in connection with Figures 4-10, such as dimensions of the cuvette and / or cavity, are equally applicable to the cuvettes described in connection with the methods and / or analyzers for analyzing blood samples of Figures 1-3, and vice versa.

[0205] Examples of methods and analyzers according to the present disclosure are set forth in the following clauses:

[0206] Clause 1. A method for analyzing a blood sample, comprising: - placing (S102) a cuvette with a sampling cavity and a sample analysis cavity on a rotatable member, said sampling cavity containing a blood sample to be analyzed; - rotating the rotatable member at a first speed in a first rotation cycle for transfer of the blood sample from the sampling cavity to the sample analysis cavity (S110); - rotating the rotatable member at a second speed in a second rotation cycle after the first rotation cycle to separate blood portions from plasma within the blood sample (S116); - acquiring second absorbance data indicative of absorbance within the plasma during the second rotation cycle using the photometer (S118); - determining a second blood parameter (S119) based on the second absorbance data, the second blood parameter being the plasma-free hemoglobin level of the blood sample; - providing (S120) an output indicative of the second blood parameter.

[0207] Clause 2. In the method according to clause 1, - rotating the rotatable member at an initial speed in an initial rotation cycle prior to a first rotation cycle (S104), the initial speed being insufficient for transfer of the blood sample from the sampling cavity to the sample analysis cavity; - acquiring initial absorbance data indicative of absorbance within the sample analysis cavity of the cuvette using a photometer and during the initial rotation cycle (S106); - determining (S108) a cuvette parameter, the cuvette being a contamination level associated with the cuvette, based on the initial absorbance data.

[0208] Clause 3. The method according to any one of clauses 1-2, wherein the acquiring step (S118) includes a step (S118A) of continuously acquiring the second absorbance data during the second rotation cycle, the method further comprising: - upon detecting stabilization of the second absorbance data, terminating the continuous acquisition of the second absorbance data (S118A). A method comprising:

[0209] Clause 4. The method according to any one of clauses 1 to 3, - acquiring (S112) first absorbance data indicative of absorbance within the blood sample in the sample analysis cavity of the cuvette using the photometer and during the first rotation cycle; - determining (S114) a first blood parameter, the first blood parameter being a total hemoglobin level of the blood sample, based on the first absorbance data.

[0210] Clause 5. In the method according to clause 4, - acquiring third absorbance data (S121) using the photometer during the second rotation cycle, the third absorbance data being indicative of a separation time of red blood cells from the plasma; - determining a third blood parameter, the erythrocyte sedimentation rate of the blood sample, based on the third absorbance data and the first absorbance data (S122); - providing (S123) an output indicative of the third blood parameter.

[0211] Clause 6. The method according to any one of clauses 1 to 5, - acquiring (S124) first image data indicative of an image of at least a portion of the blood sample in the sample analysis cavity after the second rotation cycle using an imaging device; - determining (S126) a fourth blood parameter based on the first image data, the fourth blood parameter being a hematocrit level of the blood sample; - providing (S128) an output indicative of the fourth blood parameter.

[0212] Clause 7. The method according to any one of clauses 1 to 6, - rotating the rotatable member at a third speed in a third rotation cycle after the second rotation cycle (S130), the third speed being faster than the first speed, the second speed and the initial speed; - acquiring fourth absorbance data indicative of absorbance within the blood sample in the sample analysis cavity of the cuvette using the photometer and during the third rotation cycle (S132); - determining (S134) a fifth blood parameter, the fifth blood parameter being a second plasma-free hemoglobin level indicative of fragile blood cells in the blood sample, based on the fourth absorbance data.

[0213] Clause 8. The method of any one of clauses 1-7, wherein obtaining the initial absorbance data, the first absorbance data, the second absorbance data, the third absorbance data, or the fourth absorbance data comprises measuring absorbance using three or more wavelengths.

[0214] Clause 9. The method of any one of clauses 1 to 8, wherein obtaining the initial absorbance data, the first absorbance data, the second absorbance data, the third absorbance data, or the fourth absorbance data comprises measuring absorbance data during multiple rotations of the rotatable member.

[0215] Clause 10. A method according to any one of clauses 1 to 9, wherein determining one or more of the first blood parameter, the second blood parameter, the third blood parameter, the fourth blood parameter, the fifth blood parameter, and the cuvette parameter includes integrating absorbance data acquired during multiple rotations of the rotatable member.

[0216] Clause 11. The method of any one of clauses 1 to 10, wherein the blood portion separated from the plasma is one or more of blood cells, red blood cells, white blood cells, fibrinogen, buffy coat, and lipids.

[0217] Clause 12. A blood analyzer comprising a housing, a rotatable member, a photometer, and a controller, - the rotatable member is rotatably disposed within the housing and comprises a receptacle for receiving a cuvette having a sampling cavity and a sample analysis cavity, the sampling cavity of the cuvette containing a blood sample to be analyzed; - the photometer is configured to obtain absorbance data associated with the sample analysis cavity of the cuvette; The above controller is - rotating the rotatable member at a first speed in a first rotation cycle for transport of the blood sample from the sampling cavity to the sample analysis cavity; - rotating the rotatable member at a second speed in a second rotation cycle after the first rotation cycle to separate blood portions from plasma within the blood sample; - controlling the photometer during the second rotation cycle to obtain second absorbance data indicative of absorbance within the plasma of the separated blood sample; - determining a second blood parameter, the plasma-free hemoglobin level of the blood sample, based on the second absorbance data; - providing an output indicative of said second blood parameter; a blood analyzer configured to:

[0218] Clause 13. The blood analyzer according to clause 12, wherein the controller: - rotating the rotatable member at an initial speed in an initial rotation cycle prior to a first rotation cycle, the initial speed being insufficient for transfer of the blood sample from the sampling cavity to the sample analysis cavity; - controlling the photometer during the initial rotation cycle to acquire initial absorbance data indicative of absorbance within the sample analysis cavity of the cuvette; - determining a cuvette parameter, the contamination level associated with the cuvette, based on the initial absorbance data; - providing an output indicative of said cuvette parameters; a blood analyzer configured to:

[0219] Clause 14. A blood analyzer as described in clause 12 or 13, wherein the controller is configured to control the photometer to continuously acquire the second absorbance data during the second rotation cycle, and to control the photometer to terminate the continuous acquisition of the second absorbance data upon detecting stabilization of the second absorbance data.

[0220] Clause 15. In the blood analyzer according to clauses 12 to 14, the controller - controlling the photometer to acquire first absorbance data during the first rotation cycle, the first absorbance data being indicative of absorbance within the blood sample in the sample analysis cavity of the cuvette; - determining a first blood parameter, the first blood parameter being a total hemoglobin level of the blood sample based on the first absorbance data; - providing an output indicative of said first blood parameter; a blood analyzer configured to:

[0221] Clause 16. The blood analyzer according to clause 15, wherein the controller: - controlling the photometer to obtain third absorbance data during the second rotation cycle, the third absorbance data being indicative of a separation time of red blood cells from the plasma in the sample analysis cavity of the cuvette; - determining a third blood parameter based on the third absorbance data and the first absorbance data, the third blood parameter being an erythrocyte sedimentation rate of the blood sample in the sample analysis cavity of the cuvette; - providing an output indicative of said third blood parameter; a blood analyzer configured to:

[0222] Clause 17. The blood analyzer according to any one of clauses 12 to 16, wherein the analyzer includes an imaging device, and the controller: - controlling the imaging device to acquire first image data indicative of an image of at least a portion of the blood sample in the sample analysis cavity of the cuvette after the second rotation cycle; - determining a fourth blood parameter based on the first image data, the fourth blood parameter being a hematocrit level of the blood sample; - providing an output indicative of said fourth blood parameter; a blood analyzer configured to:

[0223] Clause 18. In the blood analyzer according to any one of clauses 12 to 17, the controller - rotating the rotatable member at a third speed in a third rotation cycle after the second rotation cycle, the third speed being greater than the first speed, the second speed, and the initial speed; - controlling the photometer to acquire fourth absorbance data during the third rotation cycle, the fourth absorbance data being indicative of absorbance within the blood sample in the sample analysis cavity of the cuvette; - determining a fifth blood parameter based on the fourth absorbance data, the fifth blood parameter being a second plasma-free hemoglobin level indicative of fragile blood cells in the blood sample; a blood analyzer configured to:

[0224] Clause 19. A blood analyzer according to any one of clauses 12 to 18, wherein the photometer is configured to obtain initial absorbance data, first absorbance data, second absorbance data, third absorbance data, or a fifth absorbance data by measuring absorbance using three or more wavelengths.

[0225] Clause 20. The blood analyzer of clause 19, wherein the photometer comprises at least two light sources and at least two corresponding optical sensors, each light source emitting light at a different wavelength.

[0226] Clause 21. The blood analyzer according to clause 20, wherein the at least two light sources are light emitting diodes.

[0227] Clause 22. A blood analyzer as described in any one of clauses 12 to 21, wherein the controller is configured to control the photometer and any imaging device to measure initial absorbance data, first absorbance data, second absorbance data, third absorbance data, first image data, or fourth absorbance data during multiple rotations of the rotatable member, respectively.

[0228] Clause 23. A blood analyzer as described in clause 22, wherein the controller is configured to integrate absorbance data acquired by the photometer during multiple rotations of the rotatable member.

[0229] Clause 24. A blood analyzer according to any one of clauses 12 to 23, wherein the blood portion separated from the plasma is one or more of blood cells, red blood cells, white blood cells, fibrinogen, buffy coat, and lipids.

[0230] The use of the terms "first", "second", "third", and "fourth", "primary", "secondary", "tertiary", etc. are included to identify individual elements, but not to imply any particular order. Additionally, the use of the terms "first", "second", "third", and "fourth", "primary", "secondary", "tertiary", etc., does not indicate any order or importance, but rather the terms "first", "second", "third", and "fourth", "primary", "secondary", "tertiary", etc. are used to distinguish one element from another. It should be noted that the terms "first", "second", "third", and "fourth", "primary", "secondary", "tertiary", etc. are used herein and elsewhere merely for labeling purposes, and are not intended to indicate any particular spatial or temporal ordering. Furthermore, the labeling of a first element does not imply the presence of a second element, and vice versa.

[0231] It will be noted that the word "comprising" does not necessarily exclude the presence of other elements or steps than those listed.

[0232] It will be noted that the word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0233] While features have been shown and described, it will be understood that the features are not intended to limit the claimed disclosure, and it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the scope of the claimed disclosure. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense. The claimed disclosure is intended to cover all alternatives, modifications, and equivalents.

[0234] It may be appreciated that Figures 1-10 include some features, components, or method steps shown with solid lines and some features, components, or method steps shown with dashed lines. The features, components, or method steps shown with solid lines are the features, components, or method steps included in the broadest example. The features, components, or method steps included in dashed lines are examples that can be included in or be part of additional features, components, or method steps that may be employed in addition to the features, components, or method steps of the solid line example. It should be appreciated that not all of the method steps need to be performed. The features, components, or method steps included in dashed lines may be considered optional.

[0235] It will be noted that the word "comprising" does not necessarily exclude the presence of other elements or steps than those listed.

[0236] It will be noted that the word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

Claims

1. 1. A method for analyzing a blood sample, comprising: - placing (S102) on a rotatable member a cuvette comprising a sampling cavity and a sample analysis cavity, said sampling cavity containing the blood sample to be analyzed; - rotating the rotatable member at an initial speed in an initial rotation cycle (S104) prior to a first rotation cycle, the initial speed being insufficient for the transfer of the blood sample from the sampling cavity to the sample analysis cavity; - acquiring (S106) initial absorbance data indicative of the absorbance in or through the sample analysis cavity of the cuvette during said initial rotation cycle using a photometer; - determining cuvette parameters associated with said cuvette based on said initial absorbance data (S108); - providing an output indicative of said cuvette parameters (S109); - rotating (S110) the rotatable member in a first rotation cycle at a first speed for the transfer of the blood sample from the sampling cavity to the sample analysis cavity; - rotating the rotatable member (S116) at a second speed in a second rotation cycle after the first rotation cycle to separate blood portions from plasma within the blood sample; - acquiring second absorbance data indicative of absorbance within the plasma during the second rotation cycle using the photometer (S118); - determining (S119) a second blood parameter, which is the plasma-free hemoglobin level of the blood sample, based on the second absorbance data; - providing (S120) an output indicative of said second blood parameter.

2. 2. The method of claim 1, wherein the cuvette parameters are: - the contamination level associated with said cuvette, - absorbance data for an empty cuvette, and the presence of a cuvette in the receptacle of said rotatable member; The method of claim 1,

3. 3. The method according to claim 1, wherein the acquiring step (S118) includes the step of continuously acquiring the second absorbance data during the second rotation cycle (S118A), the method further comprising: - terminating the continuous acquisition of the second absorbance data upon detecting stabilization of the second absorbance data (S118A); A method comprising:

4. The method according to any one of claims 1 to 3, - acquiring (S112) first absorbance data indicative of absorbance within the blood sample in the sample analysis cavity of the cuvette using the photometer and during the first rotation cycle; - determining (S114) a first blood parameter, which is the total hemoglobin level of the blood sample, based on the first absorbance data.

5. 5. The method of claim 4, - acquiring (S121) a third absorbance data indicative of a separation time of red blood cells from the plasma using the photometer and during the second rotation cycle; - determining a third blood parameter, which is the erythrocyte sedimentation rate of the blood sample, based on the third absorbance data and the first absorbance data (S122); - providing (S123) an output indicative of said third blood parameter.

6. The method according to any one of claims 1 to 5, - acquiring (S124) first image data indicative of an image of at least a portion of the blood sample in the sample analysis cavity after the second rotation cycle using an imaging device; - determining (S126) a fourth blood parameter, which is the hematocrit level of the blood sample, based on the first image data; - providing (S128) an output indicative of said fourth blood parameter.

7. The method according to any one of claims 1 to 6, - rotating (S130) the rotatable member in a third rotation cycle at a third speed after the second rotation cycle, the third speed being greater than the first speed, the second speed and the initial speed; - acquiring (S132) fourth absorbance data indicative of absorbance within the blood sample in the sample analysis cavity of the cuvette using the photometer and during the third rotation cycle; - determining (S134) a fifth blood parameter based on the fourth absorbance data, the fifth blood parameter being a second plasma-free hemoglobin level indicative of fragile blood cells of the blood sample.

8. 8. The method of claim 1, wherein obtaining the initial absorbance data, the first absorbance data, the second absorbance data, the third absorbance data, or the fourth absorbance data comprises measuring absorbance using three or more wavelengths.

9. 9. The method of claim 1, wherein obtaining initial absorbance data, first absorbance data, second absorbance data, third absorbance data, or fourth absorbance data comprises measuring absorbance data during multiple rotations of the rotatable member.

10. 10. The method of claim 1, wherein determining one or more of the first blood parameter, the second blood parameter, the third blood parameter, the fourth blood parameter, the fifth blood parameter, and the cuvette parameter comprises integrating absorbance data acquired during multiple rotations of the rotatable member.

11. 11. The method of any one of claims 1 to 10, wherein the blood fraction separated from the plasma is one or more of blood cells, red blood cells, white blood cells, fibrinogen, buffy coat, and lipids.

12. A blood analyzer comprising a housing, a rotatable member, a photometer, and a controller, the rotatable member is rotatably arranged within the housing and comprises a receptacle for receiving a cuvette comprising a sampling cavity and a sample analysis cavity, the sampling cavity of the cuvette containing a blood sample to be analyzed; - the photometer is configured to acquire absorbance data relating to the sample analysis cavity of the cuvette; The controller: - rotating the rotatable member at an initial speed in an initial rotation cycle prior to a first rotation cycle, the initial speed being insufficient for transfer of the blood sample from the sampling cavity to the sample analysis cavity; - controlling said photometer during said initial spin cycle to acquire initial absorbance data indicative of absorbance within said sample analysis cavity of said cuvette; - determining cuvette parameters associated with said cuvette based on said initial absorbance data; - providing an output indicative of said cuvette parameters; - rotating the rotatable member at a first speed in the first rotation cycle for the transfer of the blood sample from the sampling cavity to the sample analysis cavity; - rotating the rotatable member at a second speed in a second rotation cycle after the first rotation cycle to separate blood portions from plasma within the blood sample; - controlling said photometer to acquire second absorbance data during said second rotation cycle, said absorbance data being indicative of absorbance within said plasma of said separated blood sample; - determining a second blood parameter, the plasma-free hemoglobin level of the blood sample, based on the second absorbance data; - providing an output indicative of said second blood parameter; a blood analyzer configured to:

13. 13. The blood analyzer of claim 12, wherein the controller is configured to control the photometer to continuously acquire the second absorbance data during the second rotation cycle and to control the photometer to terminate the continuous acquisition of the second absorbance data upon detecting stabilization of the second absorbance data.

14. 14. The blood analyzer according to claim 12, wherein the controller: - controlling said photometer to acquire, during said first rotation cycle, first absorbance data indicative of absorbance within said blood sample in said sample analysis cavity of said cuvette; - determining a first blood parameter, the total hemoglobin level of the blood sample, based on the first absorbance data; - providing an output indicative of said first blood parameter; a blood analyzer configured to:

15. 15. The blood analyzer of claim 14, wherein the controller: - controlling said photometer to acquire, during said second rotation cycle, a third absorbance datum indicative of a separation time of red blood cells from the plasma in said sample analysis cavity of said cuvette; - determining a third blood parameter, the erythrocyte sedimentation rate of the blood sample in the sample analysis cavity of the cuvette, based on the third absorbance data and the first absorbance data; - providing an output indicative of said third blood parameter; and 4. A blood analyzer comprising:

16. The blood analyzer according to any one of claims 12 to 15, further comprising an imaging device, wherein the controller: - controlling the imaging device to acquire, after the second rotation cycle, first image data indicative of an image of at least a portion of the blood sample in the sample analysis cavity of the cuvette; - determining a fourth blood parameter based on the first image data, the fourth blood parameter being a hematocrit level of the blood sample; - providing an output indicative of said fourth blood parameter; a blood analyzer configured to:

17. 17. The blood analyzer according to claim 12, wherein the controller: - rotating the rotatable member at a third speed in a third rotation cycle after the second rotation cycle, the third speed being greater than the first speed, the second speed and the initial speed; - controlling said photometer to acquire, during said third rotation cycle, a fourth absorbance data indicative of absorbance within said blood sample in said sample analysis cavity of said cuvette; determining a fifth blood parameter based on the fourth absorbance data, the fifth blood parameter being a second plasma-free hemoglobin level indicative of fragile blood cells of the blood sample; a blood analyzer configured to:

18. 18. The blood analyzer of claim 12, wherein the photometer is configured to obtain initial absorbance data, first absorbance data, second absorbance data, third absorbance data, or fifth absorbance data by measuring absorbance using three or more wavelengths.

19. 20. The blood analyzer of claim 18, wherein the photometer comprises at least two light sources and at least two corresponding optical sensors, each light source emitting light at a different wavelength.

20. 20. The blood analyzer of claim 19, wherein the at least two light sources are light emitting diodes, LEDs.

21. 21. The blood analyzer of any one of claims 12 to 20, wherein the controller is configured to control the photometer and any imaging device to measure initial absorbance data, first absorbance data, second absorbance data, third absorbance data, first image data, or fourth absorbance data, respectively, during multiple rotations of the rotatable member.

22. 22. The blood analyzer of claim 21, wherein the controller is configured to integrate absorbance data acquired by the photometer during multiple revolutions of the rotatable member.

23. 23. The blood analyzer of any one of claims 12 to 22, wherein the blood portion separated from the plasma is one or more of blood cells, red blood cells, white blood cells, fibrinogen, buffy coat, and lipids.

Images