PROTEIN S ANTIGEN-FREE (O.S)

Overview

This assay is used as an adjunct to initial testing based on the results of Protein S antigen assay. It helps in evaluating patients with history of venous thromboembolism and diagnosing Congenital / Acquired Protein S deficiency. Draw 6 mL of whole blood in 2 blue-top (Sodium Citrate) tube and gently mix by inverting. Transport the sample to the lab within 4 hours. If this isn’t possible, prepare PPP within 1 hour: First, centrifuge the sample at 3600 rpm for 15 minutes, then transfer the supernatant to a clean plastic tube. Centrifuge this supernatant again at 3600 rpm for another 15 minutes, and transfer the final supernatant (PPP) into a LABELED, clean plastic screw-capped vial. FREEZE IMMEDIATELY and ship FROZEN. DO NOT THAW.