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The VisuLize Factor VIII (F8, FVIII) ELISA Kit is intended to quantitatively measure FVIII:Ag in human plasma and factor concentrates. The biological importance of factor VIII is demonstrated in Hemophilia A and those patients suspected of thrombophilia. The laboratory diagnosis of factor VIII deficiency in Hemophilia A typically involves quantitative determination of factor VIII’s functional activity. The use of this kit in conjunction with functional assays in the area of gene therapy, assessment of factor VIII concentrates, as well as distinguishing those patients with cross-reactive material will prove useful in the area of Hemophilia-A. Additionally as documented in numerous studies, elevated levels of factor VIII is being recognized as a common risk of venous thrombosis¹, an area where Affinity’s VisuLize Factor VIII (F8, FVIII) ELISA Kit has utility.

This product is cleared for in vitro Diagnostic use by FDA, Health Canada and CE marked.  Available for sale in the United States, Canada and select European countries.

Factor VIII ELISA kit principles:

Strip wells are pre-coated with sheep polyclonal antibody to human Factor VIII. Plasma samples are diluted and applied to the wells. The FVIII:Ag present binds to the coated antibody. After washing away unbound material, peroxidase labeled sheep detecting antibody is applied and allowed to bind to the captured FVIII.  The wells are again washed and a solution of TMB (the peroxidase substrate tetramethylbenzidine) is applied and allowed to react for a fixed period of time. A blue color develops which changes to yellow upon quenching the reaction with acid. The color formed is measured spectrophotometrically in a microplate reader at 450nm. The absorbance at 450nm is directly proportional to the quantity of FVIII:Ag captured onto the well. The assay is calibrated using the calibrator plasma provided in the kit.