Which type of blood collection tube commonly used for molecular diagnostics contains EDTA?

The purple top tube is commonly used for molecular diagnostics because it contains EDTA (ethylenediaminetetraacetic acid), which acts as an anticoagulant. EDTA works by chelating calcium, which is necessary for blood clotting. This property helps preserve the integrity of the sample by preventing clot formation, making it suitable for nucleic acid extraction and analysis, which are critical in molecular diagnostics.

Additionally, the use of EDTA in these tubes supports the stability of cellular components and makes it easier to isolate DNA or RNA from the blood for testing purposes. This is particularly important in molecular diagnostics where the accurate analysis of genetic material is essential for diagnostics, such as in infections, genetic disorders, and cancer detection.

The other blood collection tube types listed have different additives for specific purposes. The red top tube typically has no additive or may contain a clot activator designed for serum collection, the green top tube generally contains heparin (another type of anticoagulant), and the blue top tube contains sodium citrate, which is primarily used for coagulation studies.