Quote Originally Posted by Relayer View Post
Sequestering agent isn't so important part of formula from patent. More interesting that developer omit any antifoggant (KBr, BZT etc)
Be careful with that statement. Most common sequestering agents buffer in the pH range and DTPA is no exception (see page 6). Choosing a different sequestering agent can give you a different pH and buffer strength! Also note that the patent lists DTPA, while the MSDS lists DTPA pentasodium salt, the first one is a strong acid while the latter one is caustic (and much easier to dissolve). If pH is suitably chosen there is a good chance that no restrainer is needed.