Nordic Biomarker’s Protein C is a chromogenic test for quantitative determination of Protein C activity in citrated human plasma which can be used as an aid in diagnosis of Protein C deficiency. Protein C deficiencies, hereditary and/or acquired, increases the risk for developing thromboembolic disease. There are two different types of Protein C deficiency; type I refers to reduced biosynthesis whereas type II is characterized by a decrease in functional activity. Protein C measures Protein C activity, thus covering both types of Protein C deficiency. Protein C consists of two components: Protein C Activator and Protein C Substrate. When a plasma sample is mixed with the Protein C Activator, all endogenous functional Protein C is activated. The level of activated Protein C in the plasma sample is quantified by adding a substrate that is specifically hydrolyzed by activated Protein C. The pNA released when the substrate is cleaved is proportional to the Protein C level in the sample.