Notes On Processing And Storage
A primary consideration is whether to collect anticoagulated or coagulated blood.
Use anticoagulated blood to get plasma, buffy coat (PBMC) and RBCs. Then, one can use the packed cell volume (containing buffy coat and RBC) as a source of RNA, DNA or viable cells.
Use coagulated blood to get serum and blood clot. Subsequently, one can use the blood clot as a source of DNA.
It is best practice to process and store whole blood samples within 1 to 24 hours of the draw. The time depends on the analytical endpoints.
Another best practice is to choose a protocol that is fit for purpose. The choice should depend on collection and transport constraints. For example, cell viability may be reduced if storage or transport is for extended periods.
- Consider all human specimens as potential biohazards (section F6.1).
From ISBER Best Practices, 2018.
Choice Of Anticoagulant
Anticoagulants differ in their mechanism of action. Therefore, one must choose anticoagulants with care to avoid problems in some lab applications. For example, the anticoagulant EDTA works by chelating metals including calcium and magnesium. This chelation may be beneficial for some blood-based assays. Yet, it has an adverse effect on others (Vaught, 2006).
References On Processing Of Blood Samples To Serum, Plasma And Buffy Coat (PBMC)
Tuck MK, Chan DW, Chia D et al, Standard operating procedures for serum and plasma collection: early detection research network consensus statement standard operating procedure integration working group. J Proteome Res. 2009 Jan;8(1):113-7.