Green vWF Antigen is a latex immunoassay for quantitative determination of vWF Antigen in citrated human plasma which can be used as an aid in diagnosis of von Willebrand disease (vWD). vWD is the most common hereditary bleeding disorder and is caused by either a quantitative or a qualitative defect of vWF. To discriminate between the different types of vWD, several different lab tests are needed. Green vWF Antigen can determine quantitative defects of vWF and is thereby an important tool to enable correct diagnosis of vWD. Green vWF Antigen consists of two components: Green vWF Antigen Latex Reagent and Green vWF Antigen Reaction Buffer. The latex reagent contains sub-micron sized polystyrene particles to which monoclonal antibodies specific for vWF are coupled. When the latex reagent is exposed to vWF in the presence of the reaction buffer, the particles will agglutinate and the light-scattering of the solution increase. The level of agglutination is proportional to the amount of vWF in the sample.