Extracting Plasma from frozen Blood samples - (Mar/23/2011 )

Hi everyone

My lab recently recieved a number of frozen blood samples from one of our collaborators overseas in purple-topped EDTA tubes. I was wondering whether anyone on this forum has sucessfully extracted plasma from a frozen blood sample? Logic tells me that this should be impossible due to haemolysis, but my supervisor wants me to look into it....

Does anyone have any suggestion?

Although, I haven't extracted plasma anytime, I think extraction should not be difficult cause you already have EDTA in your tubes. So, all you have to do, is thaw the tube and spin it down.

Try to thaw the blood and use a ficoll or histo paqe gradient for the isolation of the plasma and/or buffy coat. It will be hard because of the haemolysis, but give a try.If your lab will receiving more samples the blood can be send overnight at RT or with blue ice pack so it is keep cold but not frozen and the isolation of PBLs and Plasma will be easier.

MikeP on Wed Mar 23 17:16:01 2011 said:

There is no way to get a real plasma in your situation because your sample is freezed. Red blood cells are lyzed in any case even you added some glycerol in the sample.

If your boss is fine with the hemoglobin released from erythrocytes, you can try to extract plasma-like by 2 step of centrifugation after thawing at room temperature.
-Centrifuge at 500g for 10 min to remove cells
-centrifuge at 7000-1000g to remove membranes.

Thanks guys. I thought as much. I've asked our collaborators to send us already spun down blood for the next batch now.

Thanks again