Specimen Containers


Red-top tube :

Contains no anticoagulant or preservative.

Use

Serum or clotted whole blood. Scrum must be separated from cells within 30 to 60 minutes of venipuncture. Send scrum in a plastic transport tube.

Mottled red/gray, gold, or cherry red-top (gel -barrier) tube :

Contains clot activator and gel for separating serum from cells, but not anticoagulant. Do not use gel-barrier tubes to submit specimens for therapeutic drag monitoring. Always check the test description to determine whether a gel-barrier tube is acceptable.

Use

Serum. May be used for assays requiring serum unless otherwise staled. Separate scrum from cells within 15 to 30 minutes of venipuncture (see Preparing Scrum.) Serum may be sent in the centrifuge rube with an intact barrier (correct separation upon centrifugation) between cells and serum or in a plastic transport tube. If specimen is centrifuged before clotting is complete, a fibrin clot will form on top of the cell. This finding is frequent in hanolyzed specimens. Also, the gel barrier may not be intact and could cause improper separation of serum and cells, possibly affecting test results.

Lavender-top tube :

Contains K2 EDTA.

Use

EDTA whole blood or plasma. Send plasma in a plastic transport tube labeled "Plasma, EDTA." Send whole blood in a lavender-top tube.

Gray-top tube :

Contains sodium fluoride (a preservative) and potassium oxalate (an anticoagulant).

Use

Sodium fluoride whole blood or plasma. Send plasma in a plastic transport tube labeled "Plasma, Sodium fluoride." Send whole blood in a gray-top tube.

Blue-top tube :

Contains sodium citrate. Be sure to use only tubes with a 3.2% sodium citrate concentration. These are easily identified by the yellow diagonal stripes on the label.

Use

Sodium citrate plasma. Send plasma in a plastic transport tube labeled "Plasma, Sodium Citrate." Send whole blood in a blue-top tube.

Green-top tube :

Contains sodium heparin or lithium heparin.

Use

Heparinized whole blood or plasma. Send plasma in a plastic transport tube labeled "Plasma, Sodium Heparin" or "Plasma, Lithium Heparin." Send whole blood in a green-top tube.

Yellow-top tube :

Contains acid citrate dextrose (ACD) solution.

Use

ACD whole blood. Send whole blood in a yellow -top tube.

Royal blue-top tube :

Contains sodium EDTA for trace metal studies.

Use

EDTA whole blood or plasma. Send whole blood in a royal blue-top tube. Send plasma ins plastic transport tube labeled "Plasma, EDTA from royal blue".

Plasma Preparation Tube (PPTTM) :

Contains EDTA.

Use

EDTA plasma for molecular diagnostic tests (eg, polymerase chain reaction (PCR) and/or branched DNA amplification (bDNA) techniques). Upon centrifugation, a gel barrier is formed between the plasma and the cellular components of the blood. The tube can be sent directly to the lab without transferring to a secondary tube. Plastic tubes can be frozen at -80°C without risk.