Human FVIIa Chromogenic Activity Assay KitThe Human FVIIa Chromogenic Activity Assay Kit is developed to determine human FVIIa activity in plasma and cell culture supernatants. The assay couples immunofunctional and indirect amidolytic assay. A polyclonal antibody specific for human FVIIa has been pre-coated onto a microplate and FVIIa is bound to the immobilized antibody. The assay measures the ability of FVIIa to activate factor X (FX) to factor Xa. The amidolytic activity of the FVIIa is quantitated by the amount of FXa produced using a highly specific FXa substrate releasing a yellow para-nitroaniline (pNA) chromophore. The change in absorbance of the pNA at 405 nm is directly proportional to the FVIIa enzymatic activity.