Here is a useful program for calculating free/bound ions in the presence of multiple chelators and metals, including EGTA, calcium and magnesium:

http://web.stanford.edu/~cpatton/webmaxcS.htm

Some introduction and background can be found on the home page:

http://web.stanford.edu/~cpatton/maxc.html

Hopefully these links will be of some help,

good luck!

Here is a useful program for calculating free/bound ions in the presence of multiple chelators and metals, including EGTA, calcium and magnesium:

http://web.stanford.edu/~cpatton/webmaxcS.htm

Some introduction and background can be found on the home page:

http://web.stanford.edu/~cpatton/maxc.html

Hopefully these links will be of some help,

good luck!

Thanks Ilari!