$0.00
Technochrom® anti-Xa is a system of reagents for the chromogenic determination of direct and indirect Xa inhibitors in human citrated plasma. The assay is based on the inhibition of activated factor X (FXa) by Antithrombin (AT) in the presence of heparin as measured by a chromogenic FXa substrate.
Reagent 1 (R1) | 1 x 20 ml, anti-Xa buffer, TRIS-EDTA buffer; pH 8.4; contains sodium azide (<1g/l) as a preservative |
---|---|
Reagent 2 (R2) | 1 x 4 ml, Bovine Factor Xa, lyophilized; 1 vial; about 24 nkat |
Reagent 3 (R3) | 1 x 4 ml, Chromogenic substrate, lyophilized; 1 vial; 4.8 mg |
[Xa-Inhibitor] + Xa (excess) | → | [Xa-Inhibitor – Xa] + Xa (residual) |
Xa (residual) + substrate | → | pNA |
The amount of pNA, released by enzymatic hydrolysis, is measured at 405 nm. There is an inverse relationship between the amount of heparin present in the sample and color development.
Calibration Curve
Precision
Reproducibility was determined with different samples (in series and day to day). The following results were obtained:
Intra assay | Intra assay | ||||
---|---|---|---|---|---|
CV% | N | CV% | N | ||
LMW level 1 (1.37 u/ml) | 1.6% | 24 | LMW level 1 (1.36 u/ml) | 1.5% | 6 |
LMW level 2 (0.52 u/ml) | 2.5% | 24 | LMW level 2 (0.37 u/ml) | 2.5% | 6 |
UFH level 1 (1.26 u/ml) | 0.7% | 24 | UFH level 1 (1.45 u/ml) | 2.6% | 6 |
UFH level 2 (0.42 u/ml) | 2.1% | 24 | UFH level 2 (0.06 u/ml) | 5.7% | 6 |