Is this an electroporation protocol for bacterial cells, yeast cells, or mammalian cells?

Typically for bacterial cells, the cell mass is washed several times in cold distilled water in an attempt reduce the salts and prevent arcing. 

Dear Dhirend,

I think EDTA or EGTA is used following electroporation to chelate extracellular calcium. Electroporation using large amounts electrical pulses breaks down the membrane and that allows the passage of the molecules from extracellular space into the cytoplasm. This process allows not only molecules of interest but also influx of components extracellular solution, such as calcium. Although high calcium influx is required for initial membrane repair response, prolonged influx of calcium can also prolong cell death. Therefore, a subsequent wash with calcium chelators can help prevent subsequent death of cells. I can't see any specific role for TRIS apart from buffering pH.

I do single cell electroporation and I also use EGTA in my pipette solution, and it works very well. See below.

best wishes, Refik

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