Abstract: The invention is a method, reagent and test cartridge for the determination of the clotting time of a blood sample by means of a reagent containing tissue factor and a sulfatide. In an alternative embodiment, the reagent may contain tissue factor and at least one of the group consisting of a phosphatide and a sulfatide. This invention is preferably used to monitor the effectiveness of heparin therapy in patients that have been administered low to moderate heparin doses to achieve blood heparin levels from 0 to about 3 U/mL, and may also be used for determining clotting time at higher heparin levels of up to about 6 U/mL.

Abstract: The invention is a method, reagent and test cartridge for the determination of the clotting time of a blood sample by means of a reagent containing tissue factor and a sulfatide. In an alternative embodiment, the reagent may contain tissue factor and at least one of the group consisting of a phosphatide and a sulfatide. This invention is preferably used to monitor the effectiveness of heparin therapy in patients that have been administered low to moderate heparin doses to achieve blood heparin levels from 0 to about 3 U/mL, and may also be used for determining clotting time at higher heparin levels of up to about 6 U/mL.

Abstract: The invention is a method, reagent, test cartridge and device for the determination of fibrinogen in a sample, such as undiluted blood and blood plasma. The method utilizes a reagent comprising thrombin and a thrombin inhibitor that slows the enzymatic conversion of fibrinogen to fibrin, and thus slows clotting in samples. This is particularly useful for determining fibrinogen in undiluted blood and blood plasma. Fibrinogen assay reagents comprising at least one thrombin inhibitor and thrombin, and test cartridges containing the reagents for automated analysis of fibrinogen are disclosed, along with automated devices using said reagent and test cartridges for the devices.

Abstract: An ion exchange method for the separation of hemoglobin A.sub.2 from other hemoglobin components normally present in human blood involves the use of three buffer solutions in succession, with specified ionic strengths and pHs. The first has a phosphate buffer at 1 to 20 mM and a pH of 6.5 to 6.9; the second has phosphate buffer at 15 to 55 mM and a pH of 6.4 to 6.8; and the third has phosphate buffer at 60 to 100 mM and a pH of about 6.4 to 6.8. The first is continued until substantially all hemoglobin A.sub.1a and A.sub.1b has eluted from the column, the second until substantially all A.sub.1c, F, and A.sub.0 is eluted, and the third for the elution of A.sub.2.

Abstract: An ion exchange method for the separation of hemoglobin A.sub.2 from other hemoglobin components normally present in human blood involves the use of three buffer solutions in succession, with specified ionic strengths and pHs. The first has a phosphate buffer at 1 to 20 mM and a pH of 6.5 to 6.9; the second has phosphate buffer at 15 to 55 mM and a pH of 6.4 to 6.8; and the third has phosphate buffer at 60 to 100 mM and a pH of about 6.4 to 6.8. The first is continued until substantially all hemoglobin A.sub.1a and A.sub.1b has eluted from the column, the second until substantially all A.sub.1c, F, and A.sub.0 is eluted, and the third for the elution of A.sub.2.