EGTA

EGTA 0.5M

100 ml solution

19g EGTA (MW 380g/mol) ddH2O to 90ml adjust pH 7.5/8.0 with solid NaOH (>4g) adjust volume to 100ml

MW:
Concentration: M
to make: mL
start with: mL
add: g EDTA, adjust pH to 7.5 or 8 with NaOH pellets, then bring to final volume

Note: EGTA will not go into solution without NaOH. Once the pH has been raised sufficiently it dissolves quickly. For pH 7.5 the exact amount required is slightly above 4g. Add 3.5-4g immediately, then proceed carefully not to overshoot the desired pH.

from http://www.researchgate.net/post/How_can_I_dissolve_EGTA