I use PEG for gene transformation of petunia protoplasts.
I use PEG4000...
When washing is done, the cells aggregate and eventually die.
I guess it's because the concentration of the cells are too high
they get crushed while centrifuging..
But I saw pictures of cells exhibiting GFP with high density.
This time, it was about 233 x 10(4) cells just before I treated them with PEG.
How can I prevent them from aggregation?
I really need to keep the cells alive so I can see fair efficiencies of transformation..