Systems and methods for measuring liver enzyme levels in blood
A disposable test cartridge to determine the concentration of one or more liver enzymes in a blood sample includes a cartridge body having a plurality of chambers where at least one of the chambers contains a reactant mixture that reacts when catalyzed by one of the liver enzymes ALT, AST, ALP, or GGT in a blood sample forming a reaction solution, a removable cartridge cover connected to the cartridge body, and a test strip module connected to the cartridge body. The test strip module containing at least one analyte test strip configured for receiving a portion of the reaction solution and electrochemically measuring at least one analyte that is a reaction product in the reaction solution.
1. A disposable test cartridge for use in a point-of-care analyzer to determine the concentration of one or more liver enzymes in a blood sample, the disposable test cartridge comprising:
a cartridge body having a plurality of chambers wherein each of the plurality of chambers has an opening at a top of the cartridge body and at least one of the plurality of chambers contains a reactant mixture capable of undergoing a chemical reaction when combined with a blood sample forming a reaction solution containing at least one reaction product, the reactant mixture containing chemicals specific for being catalyzed by one of the liver enzymes alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), or gamma-glutamyl transferase (GGT) in the blood sample;
a removable cartridge cover connected to the cartridge body and covering the plurality of chambers, the removable cartridge cover having a capillary-receiving aperture and a capillary element removably insertable into the cartridge cover, the capillary element configured for obtaining a blood sample; and
a test strip module directly connected to the cartridge body and containing at least one analyte test strip configured for receiving a portion of the reaction solution and measuring at least one analyte, the at least one analyte being the at least one reaction product.
2. The disposable test cartridge of claim 1 wherein the reactant mixture containing chemicals specific to the determination of ALT includes L-alanine and α-ketoglutarate.
3. The disposable test cartridge of claim 1 wherein the reactant mixture containing chemicals specific to the determination of AST includes L-aspartate and α-ketoglutarate.
4. The disposable test cartridge of claim 1 wherein the reactant mixture containing chemicals specific to the determination of AST includes L-aspartate, α-ketoglutarate and oxaloacetate decarboxylase.
5. The disposable test cartridge of claim 1 wherein the reactant mixture containing chemicals specific to the determination of ALP includes sodium phenyl phosphate or its derivatives.
6. The disposable test cartridge of claim 1 wherein the reactant mixture containing chemicals specific to the determination of GGT includes L-glutamic acid gamma-anilide or its derivatives and glycylglycine.
7. The disposable test cartridge of claim 1 wherein the test strip module incorporates an analyte test strip configured for measuring pyruvate or L-glutamate when the at least one of the plurality of chambers contains chemicals specific for being catalyzed by one of the liver enzymes ALT or AST.
8. The disposable test cartridge of claim 1 wherein the test strip module incorporates an analyte test strip configured for measuring phenol when the at least one of the plurality of chambers contains chemicals that are catalyzed by the liver enzyme ALP.
9. The disposable test cartridge of claim 1 wherein the test strip module incorporates an analyte test strip configured for measuring aniline when the at least one of the plurality of chambers contains chemicals that are catalyzed by the liver enzyme GGT.
10. The disposable test cartridge of claim 1 wherein the test strip module incorporates an analyte test strip having a reagent matrix disposed on a working electrode containing one of pyruvate oxidase, glutamate oxidase or glutamate dehydrogenase.
11. The disposable test cartridge of claim 1 wherein the test strip module incorporates an analyte test strip having a reagent matrix disposed on a working electrode wherein the reagent matrix does not contain an enzyme or a mediator.
12. The disposable test cartridge of claim 1 wherein the analyte test strip has an electrical contact end, a sample end and a sample receiving port spaced a predefined distance from the sample end.
13. The disposable test cartridge of claim 12 wherein the sample end includes a vent opening and a sample channel between the sample receiving port and the vent opening.
14. The disposable cartridge of claim 1 wherein the test strip module incorporates two or more analyte test strips wherein at least two of the two or more analyte test strips measures the same analyte.
15. The disposable cartridge of claim 1 wherein the test strip module incorporates two or more analyte test strips wherein each of the two or more analyte test strips measures different analytes.
16. The disposable test cartridge of claim 1 wherein the removable cartridge cover covers a top surface of the cartridge body and the test strip module is connected to a side surface of the cartridge body, whereby the at least one analyte test strip is laterally spaced from the cartridge cover capillary-receiving aperture.
17. A method of determining the concentration of one or more liver enzymes in a blood sample, the method comprising:
providing the disposable test cartridge of claim 1 , wherein the plurality of chambers comprises a reactant chamber containing predefined chemicals that are catalyzed by one of the liver enzymes ALT, AST, ALP, or GGT in the blood sample, and wherein the disposable test cartridge further comprises a blood sample receiving chamber;
obtaining the blood sample and placing at least a portion of the blood sample in the sample receiving chamber;
diluting the blood sample forming a diluted blood sample;
disposing a predefined amount of the diluted blood sample into the reactant chamber;
allowing a reaction between the predefined chemicals and the diluted blood sample to continue for a predefined time period forming a reaction solution containing at least one reaction product;
transferring a portion of the reaction solution to the analyte test strip capable of measuring an amount of the at least one reaction product in the reaction solution;
measuring the amount of the at least one reaction product present in the reaction solution; and
correlating the amount of the at least one reaction product in the reaction solution to the amount of one of the liver enzymes ALT, AST, ALP, or GGT in the blood sample.
18. The method of claim 17 wherein the measuring step further includes measuring an amount of one of pyruvate, glutamate, phenol, or aniline in the reaction solution.
19. The method of claim 18 wherein the correlating step further includes correlating the amount of one of pyruvate, glutamate, phenol, or aniline in the reaction solution to the amount, respectively, of ALT, AST, ALP, or GGT in the blood sample.
20. The method of claim 17 , the measuring step comprising an electrochemical measurement technique to measure the at least one reaction product.
21. The method of claim 17 , the measuring step comprising amperometry to measure the at least one reaction product for the determination of ALT, AST, ALP, or GGT.
22. The method of claim 17 , the measuring step comprising linear sweep voltammetry to measure the at least one reaction product for the determination of ALP.
23. A disposable cartridge kit for use in a point-of-care analyzer to determine the concentration of one or more liver enzymes in a blood sample, the disposable cartridge kit comprising:
a disposable test cartridge comprising:
a cartridge body having a plurality of chambers wherein each of the plurality of chambers has an opening at a top of the cartridge body and at least one of the plurality of chambers contains a reactant mixture capable of undergoing a chemical reaction when combined with a blood sample forming a reaction solution containing at least one reaction product, the reactant mixture containing chemicals specific for being catalyzed by one of the liver enzymes ALT, AST, ALP, or GGT in the blood sample;
a removable cartridge cover connected to the cartridge body and covering the plurality of chambers, the removable cartridge cover having a capillary-receiving aperture and a removable capillary element removably insertable into the cartridge cover, the capillary element configured for obtaining a blood sample;
a disposable pipette tip disposed in one of the plurality of chambers; and
a test strip module directly connected to the cartridge body and containing at least one analyte test strip configured for receiving a portion of the reaction solution and measuring at least one analyte, the at least one analyte being the at least one reaction product.
24. The kit of claim 23 further comprising instructions on the use of the disposable test cartridge and use of the capillary element.
25. The kit of claim 23 wherein the removable cartridge cover covers a top surface of the cartridge body and the test strip module is connected to a side surface of the cartridge body, whereby the at least one analyte test strip is laterally spaced from the cartridge cover capillary-receiving aperture.
26. A method of electrochemically determining the concentration of one or more liver enzymes in a blood sample using a point-of-care analyzer, the method comprising:
providing a point-of-care analyzer;
obtaining a disposable test cartridge for use in the point-of-care analyzer, the disposable test cartridge comprising:
a cartridge body having a plurality of chambers wherein each of the plurality of chambers has an opening at a top of the cartridge body and at least one of the plurality of chambers contains a
reactant mixture capable of undergoing a chemical reaction when combined with a blood sample forming a reaction solution containing at least one reaction product, the reactant mixture containing chemicals specific for being catalyzed by one of the liver enzymes ALT, AST, ALP, or GGT in the blood sample;
a removable cartridge cover connected to the cartridge body and covering the plurality of chambers, the removable cartridge cover having a capillary-receiving aperture and a removable capillary element removably insertable into the cartridge cover, the capillary element configured for obtaining a blood sample;
a disposable pipette tip disposed in one of the plurality of chambers; and
a test strip module directly connected to the cartridge body and containing at least one analyte test strip configured for receiving a portion of the reaction solution and measuring at least one analyte, the at least one analyte being the at least one reaction product;
removing the capillary element from the removable cartridge cover, receiving a blood sample in the capillary element and replacing the capillary element containing the blood sample into the removable cartridge cover;
placing the disposable test cartridge into the point-of-care analyzer; and initiating a test cycle in the point-of-care analyzer.
27. The method of claim 26 wherein the initiating step further includes:
aspirating the blood sample from the capillary element into a bottom of a chamber directly below the capillary element; removing the
cartridge cover from the cartridge body;
attaching the pipette tip to an automated pipettor device within the point-of-care analyzer;
diluting the blood sample by pipetting a predefined amount of a diluent from another of the plurality of chambers and depositing the predefined
amount into the chamber containing the blood sample forming a diluted blood sample;
removing a predefined amount of the diluted blood sample and depositing the predefined amount of the diluted blood sample by pipetting the predefined amount into another of the plurality of chambers containing the reactant mixture of chemicals specific for being catalyzed by one of the liver enzymes ALT, AST, ALP, or GGT in the blood sample forming a reaction solution;
after a predefined reaction time, removing a predefined amount of the reaction solution and depositing onto the at least one analyte test strip to measure the at least one analyte;
measuring the amount of the at least one analyte in the reaction solution; and
correlating the amount of the at least one analyte in the reaction solution to the amount of one of the liver enzymes ALT, AST, ALP, or GGT in the blood sample.
28. The method of claim 26 wherein the measuring step includes measuring the amount of one of pyruvate, glutamate, phenol, or aniline in the reaction solution.
29. The method of claim 28 , the measuring step comprising amperometry to measure the at least one reaction product for the determination of ALT, AST, ALP, or GGT.
30. The method of claim 28 , the measuring step comprising linear sweep voltammetry to measure the at least one reaction product for the determination of ALP.
31. The method of claim 26 wherein the removable cartridge cover covers a top surface of the cartridge body and the test strip module is connected to a side surface of the cartridge body, whereby the at least one analyte test strip is laterally spaced from the cartridge cover capillary-receiving aperture.