Antithrombin (AT) activity is measured in citrated plasma for diagnosis of AT deficiency. MediRox AT liquid reagent is a ready-to-use chromogenic kit based on bovine FXa and chromogenic FXa substrate.
Liquid components, ready to use
FXa-based AT reagents
Insensitiv to Heparin Cofactor II (HCII)
Detects both type I and type II AT deficiencies
AT is the primary physiological inhibitor of thrombin and FXa in plasma, and thereby effectively regulates blood coagulation. An inherited AT deficiency is often associated with thromboembolic disease, and acquired deficiencies may occur in liver disease and disseminated intravascular coagulation.
AT activity is determined in a two-stage chromogenic assay as follows:
An excess of FXa is added to citrated plasma in the presence of heparin. The residual FXa activity is determined from the hydrolysis of a chromogenic FXa Substrate, which results in the release of free p-nitroaniline (pNA). The amount of pNA is measured by absorbance at 405 nm and the result is inversely proportional to the amount of AT present in citrated plasma, and expressed as % AT activity.
Hep + citrated plasma (AT) + FXa (excess) —–> Hep-AT-FXa + FXa residual
FXa residual + Chromogenic Substrate —–> pNA + peptide
Sensitivity & specificity
Details & typical data
|Product form:||Liquid components|
• FXa reagent: 6 mL
• Chromogenic substrate: 3 mL
• Other filling volumes available upon request
|Additional products needed:||
• Sample Diluent, 0,9 % NaCl (MRX184)
• Eximius Control Basic or Plus (L1/L2/L3) (MRX170-MRX173, MRX180-MRX183)
• Scandinavian Controls Basic, Multi and Multi Plus (L1/L2) (GHI163/GHI169; GHI164/GHI170; GHI164 GHI170)
• AT Calibrator (MRX1201), Multi Calibrator I (MRX1202) or Multi Calibrator II (MRX1203)
Not affected by the possible interferents:
UFH and LMW heparin <4,0 IU/mL; Bilirubin <0,4 g/L; triglycerides <5 g/L; hemoglobin <1,5 g/L
Stability & storage
|Shelf-life:||24 months at 2-8 °C|
|Open vial stability:||30 days at 2-25 °C|
|Reference number||Product description||Pack size|
|MRX1200||Antithrombin FXa (reagent + substrate)||6x6 mL FXa + 3x3 mL substrate|
|MRX170||Eximius Control Basic, L1+L2+L3||4+4+2x1 mL|
|MRX171/172/173||Eximius Control Basic, L1/L2/L3||10x1 mL pack per level|
|MRX180||Eximius Control Plus, L1+L2+L3||4+4+2x1 mL|
|MRX181/182/183||Eximius Control Plus, L1/L2/L3||10x1 mL pack per level|
|GHI163/169||Scandinavian Control Basic, L1/L2||10x1 mL pack per level|
|GHI162/167B||Scandinavian Control Multi, L1/L2||10x1 mL pack per level|
|GHI164/170||Scandinavian Control Multi Plus, L1/L2||10x1 mL pack per level|
|MRX1201||AT Calibrator||1x1 mL|
|MRX1202||Multi Calibrator I (AT, fibrinogen, D-dimer)||1x1 mL|
|MRX1203||Multi Calibrator II (PT Quick, AT, fibrinogen)||1x1 mL|
|MRX184||Sample Diluent (0,9% NaCl)||1x8 mL|
MRX AT product line
MRX1200Antithrombin Liquid Kit
FXa 6x6 mL
FXa substrate 3x3 mL
MRX171Eximius Control Basic L1
MRX172Eximius Control Basic L2
MRX173Eximius Control Basic L3
MRX181Eximius Control PLUS L1
MRX182Eximius Control PLUS L2
MRX183Eximius Control PLUS L3
All Coagulation Reagents
Latex-based liquid components for quantifying free Protein S in human citrated plasma using readers with wavelengths 600-800nm.
MRX Fib Clauss
Lyophilised reagents for quantifying fibrinogen in human citrated plasma, according to the Clauss method.
MRX PT Owren’s
The predominantly used PT method in the Nordics as it is less sensitive to interferences. The assay can be used with both whole blood and plasma.
MRX Thrombin Time
Two different lyophilised reagents for detection of fibrinogen abnormalities, and the presence of heparin and other thrombin inhibitors in human citrated plasma.
Liquid compontent kits containing phospholipid extract and silica contact activator. Sensitive to heparin as well as factors and insensitive to lupus anticoagulant.
Latex-based liquid components for quantifying D-dimer fragments in human citrated plasma using readers with wavelengths 350-900nm.
MRX PT Quick
PT reagent from rabbit brain origin with an ISI ~1 for responsive determination of Prothrombin Time in citrated human plasma.