LabCorp screw-capped purple frozen plastic transport tube labelled as PPP Na Citrate plasma
Double spin, separate and freeze.
LabCorp Burlington (164517); R-NX
Days Set Up:
1 - 3 days
Total: In newborns, total PS levels are lower than in adults (12% to 60%). Levels gradually reach adult ranges by six months of age
Collection/ Processing Details:
Useful for: Confirmation and characterization of protein S (PS) congenital deficiency
Platelet poor citrated plasma samples (PPP) should be obtained by double centrifugation. Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate. Evacuated collection tubes must be filled to completion to ensure a proper blood to anticoagulant ratio. The sample should be mixed immediately by gentle inversion at least six times to ensure adequate mixing of the anticoagulant with the blood. A discard tube is not required prior to collection of coagulation samples, except when using a winged blood collection device (ie, "butterfly"), in which case a discard tube should be used.
Centrifuge for 10 minutes and carefully remove 2/3 of the plasma using a plastic transfer pipette, being careful not to disturb the cells.
Deliver to a plastic transport tube, cap, and recentrifuge for 10 minutes. Use a second plastic pipette to remove the plasma, staying clear of the platelets at the bottom of the tube. Transfer the plasma into a LabCorp frozen purple tube with screw cap. Freeze immediately and maintain frozen until tested.
If the patient's hematocrit exceeds 55%, the volume of citrate in the collection tube must be adjusted.
Total and Free PS antigens: latex immunoassay
Free PS: EIA after C4b-BP complexed PS is prepcipitated out with polyethylene glycol.