RAPID BLOOD TESTING SYSTEM
20220266242 · 2022-08-25
Inventors
Cpc classification
B01L2300/045
PERFORMING OPERATIONS; TRANSPORTING
B01L3/5027
PERFORMING OPERATIONS; TRANSPORTING
B01L2200/16
PERFORMING OPERATIONS; TRANSPORTING
B01L2300/049
PERFORMING OPERATIONS; TRANSPORTING
G01N2035/00237
PHYSICS
B01L2200/0684
PERFORMING OPERATIONS; TRANSPORTING
G01N2035/00148
PHYSICS
B01L2400/0481
PERFORMING OPERATIONS; TRANSPORTING
B01L2400/0683
PERFORMING OPERATIONS; TRANSPORTING
B01L3/502715
PERFORMING OPERATIONS; TRANSPORTING
B01L2300/087
PERFORMING OPERATIONS; TRANSPORTING
B01L2400/0638
PERFORMING OPERATIONS; TRANSPORTING
International classification
B01L3/00
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A point-of-care testing (POCT) system comprising an analyzer, a measurement cartridge, and a calibration cartridge for calibrating the measurement cartridge is described. The measurement cartridge comprises at least one electrochemical sensor for measuring the one or more properties of the blood sample, and the calibration cartridge comprises a similar at least one electrochemical sensor and at least one sealed blister containing calibration fluid for calibrating the measurement cartridge. Examples of properties of the blood sample may be pH, blood gases, electrolytes, and metabolites like glucose and creatinine. The measurement cartridge may also comprise an optical chamber for measuring for example, bilirubin and hemoglobin species, for which the analyzer comprises stored calibration algorithms. The optical chamber may be disposed in any location in the measurement cartridge, for receiving a portion of the blood sample.
Claims
1. A system for measuring one or more properties of a blood sample, the system comprising: a measurement cartridge for measuring the one or more properties of the blood sample, the measurement cartridge comprising: a measurement cartridge body having an upper surface and a lower surface, the upper surface defining a sample storage well for receiving the blood sample; a measurement electrochemical sensor chamber located within the measurement cartridge body, the measurement electrochemical sensor chamber comprising at least one first electrochemical sensor for generating measurement electrical signals in response to the one or more properties of the blood sample; and a blood flow conduit for establishing fluid communication between the sample storage well and the measurement electrochemical sensor chamber; a calibration cartridge comprising: a calibration cartridge body having an upper surface and a lower surface; at least one sealed blister within the calibration cartridge body containing calibration liquid comprising known amounts of the one or more properties; and a calibration electrochemical sensor chamber located within the calibration cartridge body, the calibration electrochemical sensor chamber comprising at least one second electrochemical sensor for generating calibration electrical signals in response to the calibration liquid, wherein the at least one first and second electrochemical sensors generate similar electrical signals in response to the same amount of the same one or more properties; and a calibration liquid conduit for establishing fluid communication between the at least one sealed blister and the calibration electrochemical sensor chamber; and an analyzer comprising: a receptor for separately receiving the calibration cartridge and the measurement cartridge; means for releasing calibration liquid from the at least one sealed blister containing the calibration liquid; means for moving the calibration liquid from the at least one sealed blister to the at least one second electrochemical sensor of the calibration cartridge; means for moving the blood to the at least one first electrochemical sensor of the measurement cartridge; an electrical receiver for receiving the calibration electrical signals generated by the at least one second electrochemical sensor and for receiving the measurement electrical signals generated by the least one first electrochemical sensor; and a processor for developing a mathematical relation between the calibration electrical signals and the one or more properties in the calibration liquid, and applying the mathematical relation to the measurement electrical signals to determine the amount of the one or more properties in the blood sample.
2. The system of claim 1, wherein the at least one sealed blister consists of one sealed blister containing calibration liquid, for performing one-point calibration of the at least one first electrochemical sensor.
3. The system of claim 1, wherein the at least one sealed blister consists of two sealed blisters containing calibration liquid, for performing two-point calibration of the at least one first electrochemical sensor.
4. The system of claim 1, wherein the system comprises a plurality of calibration cartridges, for performing multi-point calibration, and wherein each of the plurality of calibration cartridges comprises a single calibration liquid blister in order to provide a plurality of calibration liquid blisters, and wherein each of the plurality of calibration liquid blisters comprises a different liquid composition.
5. The system of claim 1, wherein the one or more properties of the blood sample is pH and the at least one first electrochemical sensor and the at least one second electrochemical sensor are potentiometric electrochemical sensors.
6. The system of claim 1, wherein the measurement cartridge further comprises an optical chamber having at least one of an upper optical window and a lower optical window, the optical chamber in fluid communication with the blood flow conduit, the optical chamber for facilitating interrogation of a portion of the blood sample by electromagnetic radiation, for measuring one or more other properties of the blood.
7. The system of claim 1, wherein the means for moving the blood sample to the at least one first electrochemical sensor of the measurement cartridge comprises at least one of: an air bladder disposed in the measurement cartridge body, the air bladder in fluid communication with the sample storage well; an analyzer pump attachable to a duct of the measurement cartridge body and in fluid communication with the sample storage well; a surface of the blood flow conduit sufficiently hydrophilic to promote blood flow by capillary action; a cap for covering the sample storage well; and at least one vent defined by a surface in the cartridge body or the cap in communication with the blood flow conduit.
8. The system of claim 1, wherein the measurement cartridge further comprises one or more reagents and means for mixing the blood sample and the one or more reagents.
9. The system of claim 1, wherein the sample storage well comprises a top portion for receiving the blood sample and a bottom portion for releasing at least a portion of the blood sample to the blood flow conduit, and wherein the measurement cartridge further comprises means for mitigating blood flow out of the bottom portion of the sample storage well when blood is received in the sample storage well through the top portion.
10. The system of claim 1, wherein the measurement cartridge further comprises a cap, the cap selected from a hinged cap, a pivotal cap, a sliding cap, and a screw cap for covering the sample storage well.
11. The system of claim 1, wherein the at least one first electrochemical sensor and the at least one second electrochemical sensor are of the same type manufactured in the same batch.
12. A calibration cartridge for calibrating at least one electrochemical sensor used for measuring one or more properties of a blood sample, the calibration cartridge comprising: a calibration cartridge body having an upper surface and a lower surface; at least one sealed blister located within the calibration body and containing a calibration liquid, wherein the calibration liquid comprises a known amount of the one or more properties of the blood sample; means for releasing the calibration liquid from the at least one sealed blister; a first calibration liquid conduit in fluid communication with each of the at least one sealed blister for receiving the calibration liquid; a second calibration liquid conduit for receiving calibration liquid from each first calibration liquid conduit, wherein the second calibration conduit is closed off from any other liquid influx; an electrochemical sensor chamber in fluid communication with the second calibration liquid conduit, the electrochemical sensor chamber comprising at least one electrochemical sensor and at least one electrical output, when installed with an associated analyzer, the at least one electrical output is configured to make contact with at least one electrical input of the associated analyzer, used to measure the one or more properties of the blood sample; and a vent in communication with the electrochemical sensor chamber, wherein the vent is for releasing pressure and allowing the calibration liquid to make contact with the at least one electrochemical sensor.
13. The calibration cartridge of claim 12, wherein the calibration cartridge body does not include a sample storage well.
14. The calibration cartridge of claim 12, comprising one sealed blister containing calibration liquid, for performing one-point calibration of the at least one electrochemical sensor.
15. The calibration cartridge of claim 12, comprising two sealed blisters containing different calibration liquids, two first calibration liquid conduits, and one second calibration liquid conduit, for performing two-point calibration of the at least one electrochemical sensor.
16. The calibration cartridge of claim 15, further comprising a directional valve disposed at the junction of the two first calibration liquid conduits and the second calibration liquid conduit.
17. The calibration cartridge of claim 12, wherein the means for releasing calibration liquid comprise: (a) at least one spike for rupturing the at least one sealed blister; or (b) a weakened portion of each of the at least one sealed blister for rupturing the at least one sealed blister, wherein when the calibration cartridge is installed with an associated analyzer, a force on the at least one sealed blister is provided by the associated analyzer.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] A better understanding of the novel features and advantages of the present invention will be made by reading the detailed description of the preferred embodiments provided later, in conjunction with the accompanying drawings, in which:
[0047]
[0048]
[0049]
[0050]
[0051]
[0052]
[0053]
[0054]
[0055]
[0056]
[0057]
[0058]
[0059]
[0060]
[0061]
[0062]
[0063]
[0064]
[0065]
[0066]
[0067]
[0068]
[0069]
[0070]
[0071]
[0072]
[0073]
[0074]
[0075]
[0076]
[0077]
[0078]
[0079]
[0080]
[0081]
[0082]
[0083]
[0084]
[0085]
[0086]
[0087]
[0088]
[0089]
[0090]
[0091]
[0092]
[0093]
[0094]
[0095]
[0096]
[0097]
[0098]
[0099]
[0100]
[0101]
[0102]
[0103]
[0104]
[0105]
[0106]
[0107]
[0108]
[0109]
[0110]
[0111]
[0112]
[0113]
[0114]
[0115]
[0116]
[0117]
[0118]
[0119]
[0120]
[0121]
[0122]
[0123]
[0124]
[0125]
[0126]
[0127]
[0128]
[0129]
[0130]
[0131]
[0132]
[0133]
[0134]
[0135]
[0136]
[0137]
[0138]
[0139]
[0140]
[0141]
[0142]
[0143]
[0144]
[0145]
[0146]
[0147]
[0148]
[0149]
[0150]
[0151]
[0152]
[0153]
[0154]
[0155]
[0156]
[0157]
[0158]
[0159]
[0160]
[0161]
[0162]
[0163]
[0164]
[0165]
[0166]
[0167]
[0168]
[0169]
[0170]
[0171]
[0172]
[0173]
[0174]
[0175]
[0176]
[0177]
[0178] For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, and which are described in the following detailed description of preferred aspects of the invention.
DETAILED DESCRIPTION OF PREFERRED ASPECTS OF THE INVENTION
[0179] POCT systems comprising an analyzer, a measurement cartridge having one or more electrochemical sensors in a detection chamber, and a calibration cartridge having one or more similar electrochemical sensors are described. Systems comprising measurement cartridges having no calibration liquid blisters, and calibration cartridges having one or two calibration liquid blisters for performing one-point calibration (for offset correction) or two-point calibration (offset and slope correction), respectively, are described. Also described are systems comprising measurement cartridges having one calibration liquid blister for performing one-point calibration and calibration cartridges having two calibration liquid blisters for performing two-point calibration. Although the examples of calibration cartridges illustrate one and two calibration liquid blisters for simplicity, any number of calibration liquid blisters are considered to be within the scope of the present application. Also described are measurement cartridges comprising one or more detection chambers, wherein the one or more detection chambers comprise one or more optical chambers.
[0180] In this application, two types of cartridges are described: 1) Calibration Cartridges, and 2) Measurement Cartridges. In the calibration cartridge, no sample storage well is required, wherein the calibration liquid conduit entering the electrochemical sensor conduit is closed off from any other liquid influx, like influx of blood. For illustration, two examples of calibration cartridges, 20a and 20b, are provided, and eight examples of measurement cartridges, 10a, 10b, 10c, 10d, 10e, 10f, 10g and 10h, are provided. Various combinations of detection chambers in the measurement cartridges are provided, in order to increase the versatility of the measurement cartridges.
[0181] As used herein, the terms “comprising,” “having,” “including” and “containing,” and grammatical variations thereof, are inclusive or open-ended and do not exclude additional, un-recited elements and/or method steps. The term “consisting essentially of” when used herein in connection with a use or method, denotes that additional elements and/or method steps may be present, but that these additions do not materially affect the manner in which the recited method or use functions. The term “consisting of” when used herein in connection with a use or method, excludes the presence of additional elements and/or method steps. A use or method described herein as comprising certain elements and/or steps may also, in certain embodiments consist essentially of those elements and/or steps, and in other embodiments consist of those elements and/or steps, whether or not these embodiments are specifically referred to. The term “plurality” as used herein means more than one, for example, two or more, three or more, four or more, and the like. Unless otherwise defined herein, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. As used herein, the term “about” refers to an approximately +/−25% variation from a given value. It is to be understood that such a variation is always included in any given value provided herein, whether or not it is specifically referred to. The use of the word “a” or “an” when used herein in conjunction with the term “comprising” may mean “one,” but it is also consistent with the meaning of “one or more,” “at least one” and “one or more than one.”
[0182] The terms “operatively connected”, “in operative communication”, “in fluid communication”, “in fluid connection” or “fluidly connected” and the like, describe elements of the cartridges, for example, channels, ducts, conduits, tunnels, passageways, that permit either fluid flow, gas flow, or both fluid and gas flow between the various compartments or elements within the cartridge that are connected by the channels, ducts, conduits, tunnels, passageways and the like.
[0183] Detailed description of features of examples of the invention is described with reference to the accompanying drawings. These examples are to be considered non-limiting, and a person having ordinary skill in the art should understand that variations are within the scope of the invention, even though they are not explicitly illustrated. The same reference numerals are used for similar elements in different examples; in some cases, letters are appended to the end of the reference numerals to denote the embodiment of the invention illustrated. For example, 10a and 10b refer to two different examples of a Measurement Cartridge, and 20a and 20b refer to two different examples of a Calibration Cartridge. To maintain the distinction between a Measurement Cartridge and a Calibration Cartridge, attempts are made to provide different reference numerals for similar structures in the two different types of cartridges. It should be noted that absence of a letter after a reference numeral may refer to a structural feature of the invention incorporated in multiple examples. For easy reference, Table 1 provides a list of the reference numerals used, and a brief description of the corresponding structural features.
TABLE-US-00001 TABLE 1 Description of Structural Features. Reference Numerals Description of Structural Features 10 Generic measurement cartridge having an optical chamber, depicted in FIG. 15 10a First embodiment of a measurement cartridge 10b Second embodiment of a measurement cartridge 10c Third embodiment of a measurement cartridge 10d Fourth embodiment of a measurement cartridge 10e Fifth embodiment of a measurement cartridge 10f Sixth embodiment of a measurement cartridge 10g Seventh embodiment of a measurement cartridge 10h Eighth embodiment of a measurement cartridge 12 Source of electromagnetic radiation (EMR) of an analyzer of system 70 14 Generic receptor in an analyzer of system 70 for receiving a cartridge depicted in FIG. 15, and analyzer 80 depicted in FIGS. 18A-18C 16 Beam splitter of an analyzer of system 70 (bifurcated optical fiber shown as an example) 18 Magnifying system of an analyzer of system 70 20a First embodiment of a calibration cartridge 20b Second embodiment of a calibration cartridge 22 Two-dimensional multi-channel detector of an analyzer of system 70 24 Analog to digital converter of an analyzer of system 70 26 Processor of an analyzer of system 70 28 EMR dispersing element, e.g. a grating or a prism (a grating shown) 30a First housing member of measurement cartridge 10a 30b First housing member of measurement cartridge 10b 30c First housing member of measurement cartridge 10c 30d First housing member of measurement cartridge 10d 30e First housing member of measurement cartridge 10e 30f First housing member of measurement cartridge 10f 30g First housing member of measurement cartridge 10g 30h First housing member of measurement cartridge 10h 32 One-dimensional multi-channel detector of analyzer 70 34 Analog to digital converter of an analyzer of system 70 36 Processor of an analyzer of system 70 37 Example of a display of two-dimensional detector 22 39 Example of a display of one-dimensional detector 32 40a Second housing member of measurement cartridge 10a 40b Second housing member of measurement cartridge 10b 40c Second housing member of measurement cartridge 10c 40d Second housing member of measurement cartridge 10d 40e Second housing member of measurement cartridge 10e 40f Second housing member of measurement cartridge 10f 40g Second housing member of measurement cartridge 10g 40h Second housing member of measurement cartridge 10h 50a First housing member of calibration cartridge 20a 50b First housing member of calibration cartridge 20b 51a Sample storage well of measurement cartridge 10a 51b Sample storage well of measurement cartridge 10b 51c Sample storage well of measurement cartridge 10c 51d Sample storage well of measurement cartridge 10d 51e Sample storage well of measurement cartridge 10e 51f Sample storage well of measurement cartridge 10f 51g Sample storage well of measurement cartridge 10g 51h Sample storage well of measurement cartridge 10h 53a Top opening (or top portion) of a sample storage well 51a 53b Top opening (or top portion) of a sample storage well 51b 53c Top opening (or top portion) of a sample storage well 51c 53e Top opening (or top portion) of a sample storage well 51e 53f Top opening (or top portion) of a sample storage well 51f 53g Top opening (or top portion) of a sample storage well 51g 53h Top opening (or top portion) of a sample storage well 51h 55a Bottom opening (or bottom portion) of a sample storage well 51a 55b Bottom opening (or bottom portion) of a sample storage well 51b 55c Bottom opening (or bottom portion) of a sample storage well 51c 55e Bottom opening (or bottom portion) of a sample storage well 51e 55f Bottom opening (or bottom portion) of a sample storage well 51f 55g Bottom opening (or bottom portion) of a sample storage well 51g 55h Bottom opening (or bottom portion) of a sample storage well 51h 56a Extension of the bottom opening 55a of sample storage well 51a of cartridge 10a for connecting sample storage well 51a to blood flow conduit 259a 56b Extension of the bottom opening 55b of sample storage well 51b of cartridge 10b for connecting sample storage well 51b to blood flow conduit 259b 56e Extension of the bottom opening 55e of sample storage well 51e of cartridge 10e for connecting sample storage well 51e to blood flow conduit 259e 56f Extension of the bottom opening 55f of sample storage well 51f of cartridge 10f for connecting sample storage well 51f to blood flow conduit 259f 56g Extension of the bottom opening 55g of sample storage well 51g of measurement cartridge 10g for connecting sample storage well 51g to manifold 455g 56h Extension of the bottom opening 55h of sample storage well 51h of measurement cartridge 10h for connecting sample storage well 51h to manifold 455h 57a Sample inlet portion of cartridge 10a, which comprises some elements of the cartridge that interacts with the cap 200a 57b Sample inlet portion of cartridge 10b, which comprises some elements of the cartridge that interacts with the cap 200b 57c Sample inlet portion of cartridge 10c, which comprises some elements of the cartridge that interacts with the cap 200c 58d Sample storage well boss of cartridge 10d for increasing the sample storage well storage capacity 59a Flat surface of sample inlet portion 57a 59b Flat surface of sample inlet portion 57b 59c Flat surface of sample inlet portion 57c 60a Second housing member of calibration cartridge 20a 60b Second housing member of calibration cartridge 20b 61a Electrochemical sensor array of measurement cartridge 10a having at least one of an amperometric sensor, a conductivity sensor and a potentiometric sensor 61b Electrochemical sensor array of measurement cartridge 10b having at least one of an amperometric sensor, a conductivity sensor and a potentiometric sensor 61c Electrochemical sensor array of measurement cartridge 10c having at least one of an amperometric sensor, a conductivity sensor and a potentiometric sensor 61d Electrochemical sensor array of measurement cartridge 10d having at least one of an amperometric sensor, a conductivity sensor and a potentiometric sensor 61f Electrochemical sensor array of measurement cartridge 10f having at least one of an amperometric sensor, a conductivity sensor and a potentiometric sensor 61g Electrochemical sensor array of measurement cartridge 10g having at least one of an amperometric sensor, a conductivity sensor and a potentiometric sensor 61h Electrochemical sensor array of measurement cartridge 10h having at least one of an amperometric sensor, a conductivity sensor and a potentiometric sensor 62a Electrochemical sensor array of calibration cartridge 20a having at least one of an amperometric sensor, a conductivity sensor and a potentiometric sensor 62b Electrochemical sensor array of calibration cartridge 20b having at least one of an amperometric sensor, a conductivity sensor and a potentiometric sensor 64b Nest for seating directional valve element 69b 65g Nest for seating directional valve element 67g 66g Nest for seating directional valve element 68g 66h Nest for seating directional valve element 68h 67g First directional valve element of measurement cartridge 10g, which for example, could be an elastomeric flap 68g Second directional valve element of measurement cartridge 10g, which for example, could be an elastomeric flap 68h Directional valve element of measurement cartridge 10h, which for example, could be an elastomeric flap 69b Directional valve element of calibration cartridge 20b, which for example, may be an elastomeric flap 70 System for measuring one or more properties of blood, shown in FIG. 15 71b Smaller section of directional valve element 69b that is flappable for closing off valve seat 327b (see FIG. 8G in conjunction with FIG. 8H) 73b Larger section of the directional valve element 69b that is used to seat directional valve element 69b in receptor 64b (see FIG. 8E) 75g Sealed blister for storing calibration fluid of measurement cartridge 10g 76g Compressible blister support for supporting blister 75g over spike 277g 80 Analyzer for measuring one or more properties of blood, shown in FIGS. 18A-18C 81a Ledge in second housing member 40a of measurement cartridge 10a for housing electrochemical sensor array 61a 91a Sealed blister for storing calibration fluid of calibration cartridge 20a 92a Compressible blister support for supporting sealed blister 91a over spike 271a 93b First sealed blister for storing first calibration fluid of calibration cartridge 20b 95b Second sealed blister for storing second calibration fluid of calibration cartridge 20b 96b Compressible blister support for supporting blister 93b over spike 273b 97b Compressible blister support for supporting blister 95b over spike 275b 99a Bottom laminate for covering blister outlet conduit 301a 99b Bottom laminate for covering blister outlet conduits 307b and 309b 99g Bottom laminate for covering blister outlet conduit 431g 100a Double-sided sticky gasket of measurement cartridge 10a 100b Double-sided sticky gasket of measurement cartridge 10b 100c Double-sided sticky gasket of measurement cartridge 10c 100d Double-sided sticky gasket of measurement cartridge 10d 100e Double-sided sticky gasket of measurement cartridge 10e 100f Double-sided sticky gasket of measurement cartridge 10f 100g Double-sided sticky gasket of measurement cartridge 10g 100h Double-sided sticky gasket of measurement cartridge 10h 102a Double-sided sticky gasket of calibration cartridge 20a 102b Double-sided sticky gasket of calibration cartridge 20b 103a Cutout in double-sided sticky gasket 100a aligned with the bottom opening 55a of sample storage well 51a of cartridge 10a 103b Cutout in double-sided sticky gasket 100b aligned with the bottom opening 55b of the sample storage well 51b of cartridge 10b 103e Cutout in double-sided sticky gasket 100e aligned with the bottom opening 55e of the sample storage well 51e of cartridge 10e 103f Cutout in double-sided sticky gasket 100f aligned with the bottom opening 55f of the sample storage well 51f of cartridge 10f 103g Cutout in double-sided sticky gasket 100g aligned with the bottom opening 55g of the sample storage well 51g of cartridge 10g 103h Cutout in double-sided sticky gasket 100h aligned with the bottom opening 55h of the sample storage well 51h of cartridge 10h 105a Cutout in double-sided sticky gasket 100a for mitigating blood flow from extension 56a of bottom opening 55a during sample loading 105b Cutout in double-sided sticky gasket 100b for mitigating blood flow from extension 56b of bottom opening 55b during sample loading 105e Cutout in double-sided sticky gasket 100e for mitigating blood flow from extension 56e of bottom opening 55e during sample loading 105f Cutout in double-sided sticky gasket 100f for mitigating blood flow from extension 56f of bottom opening 55f 105g Cutout in double-sided sticky gasket 100g for mitigating blood flow from extension 56g of bottom opening 55g 105h Cutout in double-sided sticky gasket 100h for mitigating blood flow from extension 56h of bottom opening 55h 107a Cutout in double-sided sticky gasket 100a aligned with hole in sealing member 241a and corresponding hole 242a in cartridge 10a 109b Cutout in double-sided sticky gasket 100b aligned with vent 231b of cartridge 10b 109e Cutout in double-sided sticky gasket 100f aligned with vent 231e of cartridge 10e 109f Cutout in double-sided sticky gasket 100f aligned with vent 231f of cartridge 10f 113a Cutout in gasket 100a aligned with blood conduit 259a of measurement cartridge 10a 113b Cutout in gasket 100b aligned with blood conduit 259b of measurement cartridge 10b 115a Cutout in gasket 102a aligned with electrochemical sensor conduit 262a of calibration cartridge 20a 115b Cutout in gasket 102b aligned with electrochemical sensor conduit 262b of calibration cartridge 20b 116b Cutout in gasket 100b aligned with electrochemical sensor conduit 261b of measurement cartridge 10b 117a Cutout in gasket 102a aligned with blister window 291a of calibration cartridge 20a 119a Cutout in gasket 102a aligned with vent 233a of calibration cartridge 20a 119b Cutout in gasket 102b aligned with vent 233b of calibration cartridge 20b 123b Cutout in gasket 102b aligned with blister window 293b of calibration cartridge 20b 125b Cutout in gasket 102b aligned with blister window 295b of calibration cartridge 20b 127b Cutout in gasket 102b aligned with transfer conduit 315b of calibration cartridge 20b 161f Cutout in gasket 100f aligned with overlap between mixing chambers 464f and 465f 162f Cutout in gasket 100f aligned with overlap between mixing chambers 463f and 464f 163f Cutout in gasket 100f aligned with overlap between enlarged section 260f and mixing chamber 463f 165g Cutout in gasket 100g aligned with inlet 457g of manifold 455g of measurement cartridge 10g 165h Cutout in gasket 100h aligned with inlet 457h of manifold 455h of measurement cartridge 10h 167g Cutout in gasket 100g, which serves as air bladder communication port for connecting air bladder duct 421g with smaller section 268g of second directional valve element 68g 167h Cutout in gasket 100h, which serves as air bladder communication port for connecting air bladder duct 421h with smaller section 268h of second directional valve element 68h 200a Cap for closing sample inlet portion 57a of measurement cartridge 10a 200b Cap for closing inlet portion 57b of measurement cartridge 10b 200c Cap for closing inlet portion 57c of measurement cartridge 10c 200d Cap for closing sample storage well 51d of measurement cartridge 10d 200e Cap for closing sample storage well 51e of measurement cartridge 10e 200f Cap for closing sample storage well 51f of measurement cartridge 10f 200g Cap for closing sample storage well 51g of measurement cartridge 10g 200h Cap for closing sample storage well 51h of measurement cartridge 10h 203a Top side of cap 200a 203c Top side of cap 200c 203e Top side of cap 200e 203f Top side of cap 200f 203g Top side of cap 200g 203h Top side of cap 200h 205a Underside of cap 200a, comprising a cap flat surface 211a and a cap recess 215a 205c Underside of cap 200c, having a cap flat surface 211c and a cap recess 215c 205d Underside of cap 200d, comprising a cap flat surface 211c and a cap plunger 217d 205e Underside of cap 200e, comprising a cap flat surface 211e and a cap plunger 217e 205f Underside of cap 200f, comprising a cap flat surface 211f and a cap plunger 217f 205g Underside of cap 200g, having a cap plunger 217g 205h Underside of cap 200h, having a cap plunger 217h 208e Nest in top portion 30e of measurement cartridge 10e for receiving cap 200e when the cap is in a fully open configuration 209e Locking slot for capturing cap wing 210e for locking cap 200e in fully open configuration (2 shown in FIG. 13F) 210e Cap wing for locking cap 200e in fully open configuration during loading of sample storage well 51e (2 shown in FIG. 13F) 211a Cap flat surface disposed at the underside 205a of cap 200a 211c Cap flat surface disposed at the underside 205c of cap 200c 211d Cap flat surface disposed at the underside 205d of cap 200d 211e Cap flat surface disposed at the underside 205e of cap 200e 211f Cap flat surface disposed at the underside 205f of cap 200f 215a Cap recess in the underside 205a of cap 200a 215b Cap recess in the underside of cap 200b 215c Cap recess in the underside 205c of cap 200c 217d Cap plunger of cap 200d 217e Cap plunger of cap 200e 217f Cap plunger of cap 200f 217g Cap plunger of cap 200g 218e Overflow trough of sample storage well 51e 218f Overflow trough of sample storage well 51f 218g Overflow trough of sample storage well 51g 219e Overflow groove of sample storage well 51e (4 shown as an example) 219f Overflow groove of sample storage well 51f (4 shown as an example) 220e Cap plunger seal of cap plunger 217e, e.g., a rubber O-ring or a molded O-ring 220f Cap plunger seal of cap plunger 217f, e.g., a rubber O-ring or a molded O-ring 220g Cap plunger seal of cap plunger 217g, e.g., a rubber O-ring or a molded O-ring 221c Gasket for cap 200c for turning cap recess 215c into a sealed chamber when the cap is in a closed configuration 231b Cartridge vent of measurement cartridge 10b 231c Cartridge vent of measurement cartridge 10c 231d Cartridge vent of measurement cartridge 10d 231e Cartridge vent of measurement cartridge 10e 231f Cartridge vent of measurement cartridge 10f 231g Cartridge vent of measurement cartridge 10g 231h Cartridge vent of measurement cartridge 10h 232a Hinge for hingedly attaching cap 200a to body of cartridge 10a 232d Hinge for hingedly attaching cap 200d to body of cartridge 10d 232e Hinge for hingedly attaching cap 200e to body of cartridge 10e 233a Cartridge vent of calibration cartridge 20a 233b Cartridge vent of calibration cartridge 20b 235a Cap latch for engaging cap 200a to body of cartridge 10a 235d Cap latch for engaging cap 200d to body of cartridge 10d 236a Cap latch catch in body of cartridge 10a for engaging cap latch 235a 236d Cap latch catch in body of cartridge 10d for engaging cap latch 235d 241a Sealing member installed in nest 243a in measurement cartridge 10a, for frictionally engaging an analyzer pump probe, which may be a flat surface or a ball having a channel for estblishing connection between an associated analyzer pump and waste receptacle 255a 241c Sealing member installed in cartridge air inlet duct 247c in measurement cartridge 10c, for frictionally engaging the outer surface of an associated analyzer pump hollow needle 242a Hole in first housing member 30a of measurement cartridge 10a, aligned with hole in sealing member 241a 243a Nest for sealing member 241a 247c Cartridge duct for housing sealing member 241c 253a Cap vent in cartridge cap 200a of cartridge 10a 255a Waste receptacle of measurement cartridge 10a 256a Waste receptacle of calibration cartridge 20a 256b Waste receptacle of calibration cartridge 20b 258b Waste receptacle of measurement cartridge 10b 258c Waste receptacle of measurement cartridge 10c 258d Waste receptacle of measurement cartridge 10d 258e Waste receptacle of measurement cartridge 10e 258f Waste receptacle of measurement cartridge 10f 258g Waste receptacle of measurement cartridge 10g 259a Blood conduit for fluidly connecting sample storage well 51a to detection chamber 261a 259b Blood conduit for fluidly connecting sample storage well 51b to detection chamber 412b (an optical chamber) 259c Blood conduit for fluidly connecting sample storage well 51c to detection chamber 261c 259d Blood conduit for fluidly connecting sample storage well 51d to detection chamber 261d 259e Blood conduit for fluidly connecting sample storage well 51e to detection chamber (in this cartridge the detection chamber is optical chamber 412e) 259f Blood conduit for fluidly connecting sample storage well 51f to optical chamber 412f and electrochemical sensor chamber 261f 260a Enlarged section of blood conduit 259a for minimizing, mitigating, or modifying blood flow from extension 56a of bottom opening 55a of sample storage well 51a during sample loading 260e Enlarged section of blood conduit 259e for minimizing, mitigating, or modifying blood flow from extension 56e of bottom opening 55e of sample storage well 51e during sample loading 260f Enlarged section of blood conduit 259f for minimizing, mitigating, or modifying blood flow from extension 56f of bottom opening 55f of sample storage well 51f 260g Enlarged section for minimizing, mitigating, or modifying blood flow from extension 56g of bottom opening 55g of sample storage well 51g, and for fluidly connecting cutouts 105g and 165g of gasket 100g 260h Enlarged section for minimizing, mitigating, or modifying blood flow from extension 56h of bottom opening 55h of sample storage well 51h, and for fluidly connecting cutouts 105h and 165h of gasket 100h 261a Detection chamber (in this cartridge it is a biosensor chamber or an electrochemical sensor chamber) of measurement cartridge 10a 261b Biosensor or an electrochemical sensor chamber of measurement cartridge 10b 261c Detection chamber (in this cartridge it is a biosensor or an electrochemical sensor chamber) of measurement cartridge 10c 261d Detection chamber (in this cartridge it is a biosensor or an electrochemical sensor chamber) of measurement cartridge 10d 261f Electrochemical sensor chamber of measurement cartridge 10f 261g Electrochemical sensor chamber of measurement cartridge 10g 262a Electrochemical sensor chamber/conduit of calibration cartridge 20a 262b Electrochemical sensor chamber/conduit of calibration cartridge 20b 264g Larger section of first directional valve element 67g 265g Larger section of second directional valve element 68g 267g Smaller section of first directional valve element 67g 268g Smaller section of second directional valve element 68g 271a Spike for rupturing sealed blister 91a 273b Spike for rupturing the sealed blister 93b 275b Spike for rupturing the sealed blister 95b 277g Spike for rupturing the sealed blister 75g 279g Through hole in spike 277g for draining calibration fluid from ruptured blister 75g 291a Blister window in the first housing member 50a of calibration cartridge 20a for accessing sealed blister 91a 292a Through hole in spike 271a for draining calibration fluid from ruptured blister 91a 293b Blister window in the first housing member 50b of calibration cartridge 20b for accessing sealed blister 93b 295b Blister window in the first housing member 50b of calibration cartridge 20b for accessing sealed blister 95b 296b Through hole in spike 273b for draining calibration fluid from ruptured blister 93b 297b Through hole in spike 275b for draining calibration fluid from ruptured blister 95b 298g Blister window in the first housing member 30g of measurement cartridge 10g for accessing the sealed blister 75g 301a Calibration liquid conduit for receiving calibration liquid from blister 91a after the calibration liquid is released 302a Transfer conduit for transferring calibration fluid from conduit 301a to conduit 303a 303a Pre-electrochemical sensor conduit for receiving calibration fluid from transfer conduit 302a and delivering calibration fluid to electrochemical sensor conduit 262a 303b Pre-electrochemical sensor conduit for receiving calibration fluid from either transfer conduit 311b (from blister 93b) or transfer conduit 317b (from blister 95b), and delivering each calibration fluid to electrochemical sensor conduit 262b at different times 305a Post-electrochemical sensor conduit for receiving excess calibration fluid from electrochemical sensor conduit 262a 305b Post-electrochemical sensor conduit for receiving excess calibration fluid from electrochemical sensor conduit 262b 307b Blister outlet conduit for receiving calibration fluid from the ruptured blister 93b 309b Blister outlet conduit for receiving calibration fluid from the ruptured blister 95b 311b Transfer conduit for transferring calibration fluid from conduit 307b to conduit 303b 315b Transfer conduit for transferring calibration fluid from conduit 309b to transfer conduit 317b 317b Transfer conduit for transferring calibration fluid from transfer conduit 315b to conduit 303b 327b Valve seat for mating with smaller section 71b of directional valve element 69b (see FIG. 8G in conjunction with FIG. 8H) 331g Valve seat for mating with smaller section 267g of directional valve element 67g 333g Valve seat for mating with smaller section 268g of directional valve element 68g 401g Blood conduit for fluidly connecting sample storage well 51g to optical chamber 412 401h Blood conduit for fluidly connecting sample storage well 51h to optical chamber 412h 402g Blood conduit for fluidly connecting sample storage well 51g to electrochemical sensor chamber 261g 402h Blood conduit for fluidly connecting sample storage well 51h to electrochemical sensor chamber 261h 403b Pre-electrochemical sensor conduit in measurement cartridge 10b 403g Pre-electrochemical sensor conduit in measurement cartridge 10g 403h Pre-electrochemical sensor conduit in measurement cartridge 10h 405g Post-electrochemical sensor conduit in measurement cartridge 10g 405h Post-electrochemical sensor conduit in measurement cartridge 10h 411b First optical window of optical chamber 412b 411e First optical window of optical chamber 412e 411f First optical window of optical chamber 412f 411g First optical window of optical chamber 412g 411h First optical window of optical chamber 412h 412b Optical chamber of measurement cartridge 10b (may be a gasket cutout if the gasket thickness provides sufficient optical pathlength) 412e Optical chamber of measurement cartridge 10e (may be a gasket cutout if the gasket thickness provides sufficient optical pathlength) 412f Optical chamber of measurement cartridge 10f (may be a gasket cutout if the gasket thickness provides sufficient optical pathlength) 412g Optical chamber of measurement cartridge 10g (may be a gasket cutout if the gasket thickness provides sufficient optical pathlength) 412h Optical chamber of measurement cartridge 10h 413b Second optical window of optical chamber 412b 413e Second optical window of optical chamber 412e 413f Second optical window of optical chamber 412f 413g Second optical window of optical chamber 412g 413h Second optical window of optical chamber 412h 417b Air bladder of cartridge 10b 417f Air bladder of cartridge 10f 417g Air bladder of cartridge 10g 417h Air bladder of cartridge 10h 419b Air bladder laminate of air bladder 417b of cartridge 10b 419f Air bladder laminate of air bladder 417f of cartridge 10f 419g Air bladder laminate of air bladder 417g of cartridge 10g 419h Air bladder laminate of air bladder 417h of cartridge 10h 421b Air bladder duct for providing fluid connection between an air bladder 417b and an air bladder communication port 423b 421f Air bladder duct for providing fluid connection between an air bladder 417f and an air bladder communication port 163f 421g Air bladder duct for providing fluid connection between an air bladder 417g and an air bladder communication port 167g 421h Air bladder duct for providing fluid connection between an air bladder 417h and an air bladder communication port 167h 423b Air bladder communication port of a sample inlet portion 57b of cartridge 10b 423c Associated analyzer pump communication port of sample inlet portion 57c of cartridge 10c 427b One of one or more female cartridge tracks for guiding linear motion of cap 200b. In this non-limiting example, two female tracks are shown. In some embodiments, the one or more tracks may be configured as male cartridge tracks. Some embodiments may comprise one male and one female track, and if desired, the cap motion may be non-linear (i.e. curved). 431g Blister outlet conduit for receiving calibration fluid from the ruptured blister 75g 433g Transfer conduit for transferring calibration fluid from conduit 431g to pre-electrochemical sensor conduit 403g 435g Conduit for connecting conduit 402g to conduit 403g 451c Hydrophobic insert disposed close to the bottom opening 55c of the sample storage well 51c, for providing means for minimizing, mitigating, or modifying blood flow out of the sample storage well 51c 453c Nest in second housing member 40c of cartridge 10c for installing hydrophobic insert 451c 455g Manifold of extension 56g of the bottom opening 55g of sample storage well 51g of cartridge 10g, having an inlet 457g 455h Manifold of extension 56h of the bottom opening 55h of sample storage well 51h of cartridge 10h 457g Inlet of manifold 455g 457h Inlet of manifold 455h 463f First mixing chamber of measurement cartridge 10f 464f Second mixing chamber of measurement cartridge 10f 465f Third mixing chamber of measurement cartridge 10f 467b Blood shunt in measurement cartridge 10b 467f Blood shunt in measurement cartridge 10f 470h Overlap between blood conduit 402h and pre-electrochemical sensor conduit 403h of measurement cartridge 10h
Overview of Calibration Cartridges 20a and 20b as Non-Limiting Examples
[0184] Two embodiments of calibration cartridges are provided: Calibration cartridge 20a is illustrated collectively in
[0185] As an alternative to a calibration cartridge comprising two sealed calibration liquid blisters for performing two-point calibration, two calibration cartridges each comprising a single calibration liquid blister may be used, wherein each of the two calibration liquid blisters in the two calibration cartridges are located in the same position, and the liquid composition of the two calibration liquid blisters are different. An advantage to this alternative is that the analyzer only requires a single rupture mechanism. A rupture mechanism may be a stepper motor actuator, as an example, which pushes against the blister, and the same actuator may also be used to activate an air bladder, if the cartridge comprises an air bladder. Further, multi-point calibration may be performed using more than two calibration cartridges, each calibration cartridge comprising a single calibration liquid blister, wherein the single calibration liquid blisters in the more than two calibration cartridges are located in the same position, and the liquid composition of each of the single calibration liquid blisters is different. When more than one calibration cartridges, each having a single calibration blister, the calibration liquid in each calibration cartridge is released and tested sequentially.
[0186] Other measurement cartridges that may be calibrated with calibration cartridges 20a or 20b include measurement cartridge 10a (shown in
[0187] Calibration cartridge 20b, measurement cartridge 10b and analyzer 80 are used as examples to illustrate a system shown in
[0188] Calibration of one or more electrochemical sensors in electrochemical sensor array 61b of measurement cartridge 10b, using calibration cartridge 20a is described: Force from an attachment to a stepper motor, as a non-limiting example, in an associated analyzer is applied to the top portion (dome portion) of the blister 91a via blister window 291a (see
[0189] Although calibration cartridges 20a and 20b are both shown to comprise first housing members 50a and 50b attached to second housing members 60a and 60b by double-sided sticky gaskets 102a and 102b respectively, calibration cartridges comprising different housing members in terms of design and number of components are considered to be within the scope of the present application.
[0190] Calibration cartridge 20b shown collectively in
Overview of Measurement Cartridges 10a, 10b and 10c as Non-Limiting Examples
[0191] A first embodiment of a measurement cartridge 10a is illustrated collectively in
[0192] The pump probe may be a flat surface or a ball having a channel for establishing connection between an associated analyzer pump and waste receptacle 255a. After the sample storage well 51a receives blood sample, hinged cap 200a is moved from the first position to the second position shown in
[0193] Blood conduit in cartridge 10a is shown as the combination of a groove 259a in the first housing member 30a and a cutout 113a in gasket 100a, but in order to minimize sample requirement, the blood conduit may only be the gasket cutout 113a, for example 259e shown in
[0194] A third embodiment of a measurement cartridge 10c is illustrated collectively in
[0195] A second embodiment of a measurement cartridge 10b is illustrated collectively in
[0196] Measurement cartridges like 10a, 10b and 10c are discussed in PCT/CA2020/051254 filed Sep. 18, 2020. Other relevant cartridges discussed in PCT/CA2020/051254 include measurement cartridges that slide about a pivotal hinge instead of sliding along tracks.
Overview of Measurement Cartridges 10d and 10e as Non-Limiting Examples
[0197] A fourth embodiment of a measurement cartridge 10d is illustrated collectively in
[0198] A fifth embodiment of a measurement cartridge 10e illustrated collectively in
[0199] The sample storage capacity of the sample storage well 51e may be altered by changing the diameter of the well 51e. The sample storage capacity of the sample storage well 51e may also be altered without changing the diameter of the well 51e, by increasing or decreasing the depth of the well 51e. As shown in
Overview of Measurement Cartridges 10f as a Non-Limiting Example
[0200] A sixth embodiment of a measurement cartridge 10f is illustrated collectively in
[0201]
[0202] Movement of altered blood from the mixing chamber 463f is facilitated by pressurized air from air bladder 417f via air bladder duct 421f and air bladder communication port 163f. Therefore, movement of unaltered blood and movement of altered blood are two separate steps, utilizing the plunger 217f and the air bladder 417f respectively. Optional use of an associated analyzer pump instead of an air bladder 417f was previously discussed.
[0203] Illustrated in
Overview of Measurement Cartridges 10g and 10h as Non-Limiting Examples
[0204] A seventh embodiment of a measurement cartridge 10g is illustrated collectively in
[0205] Shown in
[0206] Some structural features and views are illustrated for either measurement cartridge 10g or 10h and not in both. Therefore, in order to understand the cartridges functionality, references may be made to structural features and views for either measurement cartridge 10g or 10h, and the cartridges are recognized by the letters “g” and “h” respectively. After blood is placed in the sample storage well 51g shown in
[0207] In the first stage, cap 200g is adjusted from the first position to a second position, wherein in the second position the cartridge is configured so that the plunger 217g in cap 200g displaces at least some of the blood in sample storage well 51g through bottom opening 55g. The displaced blood flows through manifold 455g (see
[0208] In the second stage, positive air pressure from, for example, an air bladder 417h pushes the blood in blood conduit 402h into electrochemical sensor chamber 261h for measurement by the one or more sensors in electrochemical sensors array 61h. Other means for pushing blood into electrochemical sensor chamber 261h includes an associated analyzer pump, as described regarding measurement cartridge 10c illustrated collectively in
[0209] As mentioned before, the major difference between measurement cartridges 10g and 10h is that cartridge 10g comprises a calibration fluid blister 75g for performing a one-point calibration. An option in cartridge 10g is inclusion of a directional valve element 67g (see
Spectroscopic Measurement
[0210] Spectroscopic measurement of a blood sample is described. Other terms like spectrophotometric, photometric or optical measurement are sometimes used instead of spectroscopic measurement. A block diagram of an example of a system 70 (lower panel) for measuring one or more analyte quantities per unit volume of blood and one or more formed element quantities per unit volume of blood is provided as a non-limiting example in
[0211] With respect to the spectroscopic measurement alone, the analyzer may comprise a source of EMR (represented by 12 in
[0212] For illustration of a method for performing spectroscopic measurement of whole blood, and by way of example which is not to be considered limiting, the PDA detector may have a pixel dispersion of 2 nanometers per pixel (i.e., the pixel or digital resolution), and the PDA detector is calibrated (i.e., wavelength calibration) to read from wavelengths 300 nanometers to 812 nanometers. Two laser beams may be used to conduct wavelength calibration, which is well known by persons having knowledge in the art (see for example U.S. Pat. Nos. 6,372,503, and 6,711,516). In this example, the center of pixel 1 is assigned a wavelength of 300 nanometers (laser #1), and the center of pixel 256 is assigned a wavelength of 812 nanometers (laser #2), thereby providing a wavelength range of 300-812 nanometers. For clarity, since the center of pixel 1 is assigned 300 nanometers, the center of pixel 2 will be assigned 302 nanometers, the center of pixel 3 will be assigned 304 nanometers and so on in increments of 2 nanometers per pixel (the pixel dispersion). The two lasers may emit EMR at any wavelength within the range of 300-812 nanometers, having sufficient spacing so that linear interpolation and linear extrapolation of wavelengths can be conducted. A person skilled in spectroscopy should appreciate that the wavelength range and spectral resolution of the PDA detector depends on several factors, for example, the semiconductor material used to construct the PDA, and diffraction grating (transmission or reflective/reflection grating) and the orientation of the grating relative to the PDA detector. The source of EMR is a major determinant of the wavelength range. Each pixel is typically scanned in microseconds, which provides sufficient time to accumulate sufficient charge on the photodiode, for example to distinguish a signal from noise and dark current, without saturating the photodiode. The time the photodiode is exposed to the EMR may be referred to as “integration time”.
[0213] Saturation, or “saturating the photodiode”, means that the photodiode has reached a maximum response in current and any additional photons impinging upon the photodiode is usually converted to heat instead of current. Because the scanning time is so short, it is reasonable to say that all the photodiodes in the PDA detector are scanned simultaneously. The photons are converted to electrical current, which is measured and digitized. In this present example, absorbance (sometimes referred to as absorption, denoted by A) may be determined, where
It is well known that transmittance is defined as the fraction of incident light which is transmitted or passes through a sample. Thus:
where
[0214] I.sub.o=the intensity of light (or EMR) impinging upon or interrogating the sample (i.e. the incident light) and
[0215] I=the intensity of light (or EMR) emerging from the sample after passing through the sample.
[0216] For calculating transmittance, the amount of EMR impinging upon the optical chamber, I.sub.o, may be measured by interrogating an optical chamber containing air. The EMR impinging upon the optical chamber, I.sub.o, may be measured before or after every sample measurement, or less frequently and stored in the processor for later use.
[0217] As an example, spectroscopic measurements are used to estimate prothrombin time (PT; usually reported as PT-INR; PT-International Normalized Ratio), activated partial thromboplastin time (aPTT), or thrombin time (TT), and since a normal PT is about 10-14 seconds, a normal ACT is about 70-130 seconds, and a normal TT is about 15-19 seconds, the measurements are performed every second. An aspect of the invention with respect to coagulation measurements, e.g. PT, ACT and TT, is to use the absorbance at one or more wavelengths or pattern recognition using absorbances at a plurality of wavelengths. Techniques of pattern recognition, combined with spectroscopy are known by those having skill in the art. An example where spectroscopy, combined with pattern recognition algorithms are used and that may be applied to the methods described herein, is provided in Zhang et. al. (Mid-Infrared Spectroscopy for Coffee Variety Identification: Comparison of Pattern Recognition Methods”, J. of Spectroscopy, Volume 2016, Article ID 7927286). As blood coagulates, the blood changes from various liquid varieties to various gel varieties, with corresponding changes in spectroscopic patterns, allowing one to use similar techniques as those used by Zhang et. al. to identify different variety of coffee beans. The specific blood coagulation time measured depends on the reagents included in the cartridge. For example, thromboplastin may be used for PT, celite or kaolin may be used for ACT, and thrombin may be used for TT.
[0218] Typically, blood coagulation time is measured using mechanical methods. For spectroscopic-based assays, citrated plasma is usually used in place of whole blood, because with whole blood, a much larger fraction of the incident EMR is scattered and absorbed by the blood cells, compared with the change in emerging EMR due to gelling of the plasma. However, separating out the plasma from the whole blood requires time and centrifugation equipment. It is well known that as plasma clots or coagulates, the absorbance at a single wavelength increases. By way of example, G. O. Gogstad et. al. (1986, “Turbidimetric Determination of Prothrombin Time by Clotting in a Centrifugal Analyzer” Clin. Chem. 32/10, 1857-1862), describe the change in absorbance spectra of plasma during coagulation. However, measurement of coagulation time using whole blood instead of plasma is more representative of in vivo coagulation. Therefore, there is a need for spectroscopic measurement of the blood coagulation time employing whole blood. In order to improve the signal to noise ratio when whole blood is used with the devices as described herein, the depth of the optical chamber should be relatively small, for example about 50-200 micrometers. The use of absorbance, reflectance or transmittance at a single wavelength to generate a clotting reaction curve (for example as shown in FIG. 1 of Gogstad et. al. 1986, using absorbance), and the calculations used to compute clotting time, are considered to be within the scope of the present invention. Gogstad et. al. also provided examples of calculations use to compute clotting time that may be used according to the methods described herein.
[0219] As an example, the source of EMR may be a tungsten lamp. U.S. Pat. No. 6,651,015 describes how spectrophotometric apparatus are calibrated for measuring properties of blood, using multi-wavelength analysis. With the use of a source of EMR like a tungsten lamp, which provides multiwavelength EMR (the tungsten lamp is polychromatic, whereas a laser is monochromatic), and the use of a linear PDA detector, the analyzer has the capacity to generate full absorbance spectra in milliseconds. Several spectra may be collected over milliseconds and the absorbances averaged to minimize noise. Mathematical smoothing techniques, which are covered extensively in the literature, may be used to minimize noise. Other mathematical techniques like the use of an order derivative of absorbance are also discussed in U.S. Pat. No. 6,651,015. Even though full absorbance spectra are obtained, selected portions of the absorbance spectra, a wavelength range of the absorbance spectra, or the full absorbance spectra, may be used in order to determine a concentration of one or more than one analyte of interest. Examples of an absorbance spectrum is provided in
[0220] Any analyte that provides an absorbance, reflection or transmission spectrum change at one or more wavelengths with a change in the concentration of the analyte may be measured by spectroscopy. Other examples of analytes include bilirubin and CO-oximetry.
Electrochemical Measurement
[0221] Electrochemical measurements are performed using electrochemical sensors installed in the detection chamber of the measurement cartridge. The electrochemical sensors may contain, without being limiting in any way, at least one of an amperometric sensor (e.g. a glucose sensor comprising an enzyme glucose oxidase or a sensor that measures pO.sub.2), a conductivity sensor (e.g. a hematocrit sensor or an electrical switch), and a potentiometric sensor (e.g. an ion-selective electrode that can measure an electrolyte or pH).
[0222] As an example, electrochemical sensor array 61b of measurement cartridge 10b, illustrated collectively in
[0223] While the above description provides example embodiments, it will be appreciated that the present invention is susceptible to modification and change without departing from the fair meaning and scope of the accompanying claims. Accordingly, what has been described is merely illustrative of the application of aspects of embodiments of the invention. Numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. Furthermore, the discussed combination of features might not be absolutely necessary for the inventive solution.