2 replies to this topic

[helencollins560]

I think i may start making my own TBE buffer rather than buy some

am i correct in thing for 10x TBE = 108g tris base, 55g boric acid, 40ml 0.5M EDTA (pH8)??

To make the 0.5M EDTA can you still make it with EDTA that is not disodium salt?

[mdfenko]

helencollins560, on 02 May 2012 - 08:47 AM, said:

To make the 0.5M EDTA can you still make it with EDTA that is not disodium salt?

yes but you will have to add base (naoh) until the edta goes into solution. add the base slowly so that you don't pass pH=8 (you won't have to monitor until the edta is nearly completely in solution).

[manueliux_06]

Hi, is correctly

TBE 10 X

108 g Tris base

55 g boric acid

40mL 0.5M EDTA, pH 8.0

Fill to 1000mL with H2O

EDTA

The disodium salt of ethylenediamine tetraacetic acid (EDTA) dissolves in water only when the pH

of the solution is adjusted to 8.0 by the addition of NaOH solution.

EDTA (ethylenediaminetetraacetic acid), 0.5 M (pH 8.0)

Dissolve 186.1 g disodium EDTA dihydrate in 700 ml water. Adjust pH to 8.0 with 10 M NaOH

(∼50 ml; add slowly). Add water to 1 liter and filter sterilize.

Begin titrating before the sample is completely dissolved. EDTA, even in the disodium salt form, is difficult to

dissolve at this concentration unless the pH is increased to between 7 and 8.