I need to get animal blood samples stabilized to extract blood plasma.
The plan is that I dilute 1.65 gramms disodium EDTA in 100 mL solvent;
and then add 100 mL of this anti-coagulant solution per 1 Liter of blood. (or proportionally less)
I made a test run creating the anti-coagulant, and it dissolves well into a clear and transparent solution.
Unfortunately, the lab I am working in does not have an Osmometer (yet?).
Any ideas whether I should dilute the EDTA in water? Or physiological saline 0,9% NaCl?
EDTA with its two sodium ions should have an osmotic effect already? Is there an easy test to measure it? Or should I mix both versions with blood and observe if the cells explode?
Thank you very much!
Adding water will not only increase the hypotonicity of the EDTA but may subsequently cause haemolysis when used. Normal saline physiologically isotonic would rather help. Thank you. Better still set up 2 controls, one with EDTA dissolved in water and another diluted in normal saline and add drops of blood and observe for haemolysis.
This stabilization plan involves unnecessary sample dilution. I suggest you work with a local clinical lab to select an optimal solution for your animal model.
- For osmolaltiy: you could collect blood directly into heparin (solid) for an un-diluted plasma (preferred option).
- If you must used EDTA, collection of blood into an EDTA-tube (solid EDTA) filled to a pre-set sample volume, will result in a known concentration of EDTA in whole blood and a predictable influence of this EDTA salt concentration on osmolality.
-Use of aqueous solutions of anticoagulants is not necessary.