Thrombin, the proteolytic enzyme that catalyzes the transformation of soluble
fibrinogen to the polymerized fibrin clot, participates in multiple reactions in blood
coagulation in addition to the clotting reaction. Although reference materials have
existed for many years, structural characterization and measurement of biological
activity have never been sufficient to permit claims of clear metrological traceability
for the thrombin preparations. Our current state-of-the-art methods for protein
characterization and determination of the catalytic properties of thrombin now make it
practical to develop and characterize a metrologically acceptable reference material and
reference measurement procedure for thrombin. Specifically, α-thrombin, the biologically
produced protease formed during prothrombin activation, is readily available and has
been extensively characterized. Dependences of thrombin proteolytic and peptide
hydrolytic activities on a variety of substrates, pH, specific ions, and temperature are
established, although variability remains for the kinetic parameters that describe
thrombin enzymatic action. The roles of specific areas on the surface of the thrombin
molecule (exosites) in substrate recognition and catalytic efficiency are described and
characterized. It is opportune to develop reference materials of high metrological order
and technical feasibility. In this article, we review the properties of α-thrombin
important for its preparation and suggest an approach suitable for producing a reference
material and a reference measurement procedure that is sensitive to thrombin’s catalytic
competency on a variety of substrates.
Correction to: Determination of serum 25-hydroxyvitamin D status among population in southern China by a high accuracy LC-MS/MS method traced to reference measurement procedure
