- Prepare 800 mL of distilled water in a suitable container.
- Add 11.7 g of EDTA to the solution.
- Slowly adjust the pH to 8.0 with 2 M NaOH. (Unless using the salt, EDTA often requires extended time and basic pH conditions to completely dissolve.) Store for up to 3 mo at 4°C.
- add 100 g EDTA and begin stirring. Adjust pH as needed to 7.2-7.4 by cautiously adding drops of 10N NaOH (or pellets). Cover and stir until completely dissolved.