Affinity Biologicals Plasma – Bethesda Assay

Affinity Biologicals is one of the top companies supplying control plasmas, deficient plasmas, calibrator plasmas for research and diagnostics. One of their more popular products is Factor Inhibitor Plasmas, meant to be used as a positive control within Inhibitor Assays. If you are searching for Factor VIII inhibitor plasmas for your research or to perform inhibitor testing, this manufacturer provides it. The neutralizing antibody activity is determined by Nijmegen-modified Bethesda Inhibitor Assay and values are reported in BU/ml. Our Inhibitor Plasmas are produced to one or more inhibitor categories: Mild (1-10BU/ml), Moderate (>11-50BU/ml) or Strong (> 50-200BU/ml); not all potencies are available for all coagulation factors.


Since different plasmas have varying concentrations of inhibitors, it is best to use those that have already been tested to measure those units. The Bethesda Assay provides this information so that your research results will be accurate and you will be able to reduce or eliminate any errors in subsequent tests. Affinity offers mild, moderate, and strong Factor Inhibitor Plasmas for you to select from. These samples are derived from normal plasma for you to conduct testing and research without any additional or unnecessary treatment to obtain objective results. In addition, each sample will contain a consistent amount of inhibitor concentrations, giving you constant precision. The Bethesda Assay measurements guard against varying concentrations in the same stock of samples.


Affinity provides both frozen andfreeze-dried (also known as lyophilized) samples so that you are provided with cost effective units. Because each lot of plasma has undergone quality control using the Nijmegen-modified Bethesda Inhibitor Assay, they can be used as positive controls in your testing. Factor Inhibitor Plasmas from Affinity Biologicals are artificially produced by the addition of heterologous neutralizing antibodies to factor deficient plasmas.  Eliminate added risksin your assays by using Affinity Biologicals Factor Inhibitor Plasmas a known trusted source in coagulation and hemostasis testing.

To find out more information about Factor Inhibitor Plasmas or the Bethesda Assay or any of Affinity Biologicals Inc.’s research products visit their website at http:/// or contact them directly at:

Affinity Biologicals Inc.

1348 Sandhill Drive

Ancaster, ON

L9G 4V5

Phone: 905 304 9896