KCT is an important assay for the detection of lupus anticoagulant LA. It is modified to increase the sensitivity for lupus anticoagulant detection. It appears to be most useful in patients with a normal or minimally abnormal aPTT. It is more sensitive in detecting antibodies to prothrombin-phospholipid complexes. 6 mL Whole blood in 2 Blue Top (Sodium Citrate) tube. Mix thoroughly by inversion. Transport to Lab within 4 hours. If this is not possible, make PPP within 1 hour of collection as follows: Centrifuge sample at 3600 rpm for 15 min. & transfer supernatant to a clean plastic tube. Centrifuge this supernatant again at 3600 rpm for 15 min. & finally transfer the supernatant (PPP) to 1 labelled clean plastic screw capped vial. FREEZE IMMEDIATELY. Ship frozen. DO NOT THAW.