Tubes used in laboratory testing

There are several types of blood collection tubes used in the medical field. Some are common and others are not. Depending on the test performed, a phlebotomist may use a variety of tubes for a single patient.

Blue-top Monoject (r) and ACD tubes are typically the most common. They are used to collect whole blood or serum for a range of special tests, including heavy metals analysis, cellular immunology and trace element analysis. These tubes are EDTA-containing, which means that they contain an anticoagulant. They need to be inverted 6-8 times immediately after collection to ensure adequate mixing with the anticoagulant.

Gold-top SST (Gel & Clot) tubes are used for whole blood and serum trace element analysis, hepatitis testing and other medical tests. These tubes contain a clot activator and separation gel. They need to be inverted 5 times to expose blood to the clot activator. This causes the blood to clot, and then centrifugation separates the clot from the serum.

Sodium Polyanethole Sulfonate, or SPS, is the anticoagulant in these tubes. It inhibits the activity of complement enzymes, a key enzyme in the coagulation process. It also has a number of other biological and medical applications.

QuantiFERON-TB Gold In-Tube (QFT-GIT) has shown high specificity for detecting M. tuberculosis infection, but a large variability in response among individuals is observed. In this study, we examined the associations between subject characteristics and discordant QFT-GIT results in 769 U.S. Navy recruits categorized by risk for M. tuberculosis infection.