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TAE Buffer - (Aug/28/2005 )

hi. I am preparing TAE buffer and would like to ask why there are still EDTA precipitates in my buffer? In making 500 ml of buffer, do i substract the volume of EDTA and glacial acetic acid to the 500 ml of water i will be adding? or still use 500 ml of water plus the added volume of EDTA and glacial acetic acid? thanks


EDTA does not dissolve until you add NaOH to the solution. While I suppose that the solid might dissolve to form TAE eventually, the normal way of making TAE involves first making 0.5M EDTA at a pH of 8.0, and mixing sufficient amounts of that solution into the final TAE buffer.


thank you for the info Sir. I just want to ask again, is it a one time that i need to check the ph? do i still need to check the ph of a 1x buffer, or just check the ph of a 50x buffer? thanks


I use a 50X stock of TAE and I've never checked the pH of 1X buffer that I make from that stock. I've never had problems with this.



you should first prepare a stock solution of EDTA at pH8, by dissolving powder in water and adding NaOH.
Then prepare your TAE buffer by adding 100ml of water, the required amounts of acetate and EDTA and complete to 500ml with water. That means that the total water used for preparation is less than 500ml.