i think it won't be a problem, especially if you keep the plasma on ice and process within 8 hours. Maybe that reference help you:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC95666/#!po=34.3750

Good luck!

Hi,

It is to my knowledge important to freeze the samples within one hour to secure the quality of the samples (in some kind of portable nitrogen device). Lower levels of the cytokines are one of the problems. We have then kept our serum samples (I thought serum was more common than plasma?) on -70 degrees Celsius for at least 6 months.

Good luck!

one of the most important things which happens, if samples are nut spun down and frozen, is that levels increase quite a bit. Keeping samples at 4°C is better than RT but still I would try to get them frozen down with 4-8 hrs. maybe one of our recent publications can also help you out;

http://www.sciencedirect.com/science/article/pii/S1046202313001096

good luck with your studies.

Maritza, I think one aspect to be considered also is how the plasma is prepared from whole blood since you wish to make sure that the level of residual blood cells, especially WBC and platelets, is minimal to avoid activation and release of cytokines in the plasma before the freezing stage. To have good removal of the platelets you may need to perform two centrifugations at 2'500 x g for 15min at RT within 2 hrs of blood collection. If the plasma is cell-free, it is more likely to be stable at room temperature, with less proteolytic activity, therefore limiting the risks of artefacts. Since I assume you will perform cytokine immunogenic assays it should be ok to keep cell-free plasma for 8 hrs before freezing. Best, Thierry

hi,

Why do not you use a gated nitrogen tank instead of ice?