Technozym® vWF:Ag ELISA is an assay kit for determination of von Willebrand Factor (vWF) antigen in plasma and concentrates. In combination with the Technozym® vWF:CBA ELISA kit classification of von Willebrand disease type 1, 2 and 3 is possible when performing research. Assay time is only 60 minutes.

  1. ELISA test strips (12) with 8 wells each, coated with polyclonal anti-vWF; the drying agent is supplied in an aluminum bag.
  2. Washing buffer concentrate: (PBS; pH 7.3); containing detergent; 0.01% merthiolate; 1 bottle, 100 ml.
  3. Incubation buffer: (PBS; pH 7.3); contains stabilizer protein; 0.01% merthiolate; dye, 1 bottle, 100 ml, ready for use.
  4. Calibrators (Standards) numbered; lyophilized; 1 bottle each. Concentrations are lot-dependent; consult label on the vial.
  5. Control plasmas “low level” and “high level” for checking purposes, lyophilized; 1 bottle each. Concentrations are lot-dependent; consult the label on the vial.
  6. Conjugate polyclonal Anti-vWF-POX; dyed blue; 1 bottle, 0.3 ml.
  7. Chromogen TMB (tetramethylbenzidine); 1 bottle, 12 ml; ready to use.
  8. Stopping solution: sulphuric acid 1.9 mol/l; 1 bottle 12ml; ready for use.
  9. Adhesive film: for ELISA test strips (2)

The von Willebrand Factor (vWF) is a large, multifunctional glycoprotein, occupying a key position in primary hemostasis. It has a multiple structure with several functions:

  • It is the carrier protein for Factor VIII in plasma; it forms a complex and thus protects Factor VIII from early proteolytic decomposition.
  • It acts as a mediator for platelet aggregation by attaching itself to platelet membrane receptors (GP Ib and GP lIb/IIIa) following previous platelet activation.
  • It plays a part in primary hemostasis by acting as a mediator between adhesioned platelets and the subendothelium (lesioned vascular wall). The von Willebrand Syndrome (vWS) is the most frequently occurring hemorrhagic disease; it may be hereditary as well as acquired, caused by quantitative or qualitative defects of the vWF.

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What is the function of von Willebrand Factor? Briefly describe von Willebrand disease.
von Willebrand factor (vWf) is a glue-like adhesive protein that is responsible for the adhesion of platelets to damaged vascular endothelium. It also carries and protects factor VIII. von Willebrand disease is a hereditary bleeding disorder caused by moderate-to-severe factor VIII deficiency and low-levels of factor VIII-related antigen (substances necessary for blood clotting). Additionally, there is insufficient von Willebrand factor which also helps blood clot. The von Willebrand factor helps platelets to stick to the blood vessel wall and to each other, which is necessary for normal blood clotting.

Visit the vWF product pages for available kits to measure vWF antigen, activity, and collagen binding.