Hello,

First you have to calculate the composition of your solution using the software computer program based on the work of Fabiato (Fabiato, A. & Fabiato, F. Calculator programs for computing the composition of the solutions containing multiple metals and ligands for experiments in skinned muscle cells. J. Physiol. 75, 463-505)

You will download references and software at this web page : http://maxchelator.stanford.edu/references.htm

You can also see the following references, were the authors performed some studies in those they calculated pCa for their solutions :

Calculated and measured [Ca2+] in buffers used to calibrate Ca2+

macroelectrodes John A.S. McGuigan, Friederike Stumpff Analytical biochemistry (2013) 436 : 29-35

Analysing force–pCa curves John S. Walker, Xiaotao Li  and

Peter M. Buttrick Muscle Res Cell Motil (2010) July ; 31(1): 59–69

Finally I advice you to use stock calcium solution already prepared (for example CaCl2 1M from Sigma Ref 21115-100ML) instead of preparing a self-made solution with calcium chloride powder. As calcium hydrates, it is very complicated to weight correctly and to have the good final concentration.

Good luck

Regards

Jean-Pierre Gomez

Dear Jeane Pierre. I did this sometime ago. Go to my Research Gate account and copy a book "Practical Mitochondriology". In the Chapter on Calcium there is a description and reference for the method.. Also, if you use ruthenium red, you must recristallise it..

Dear Jean and Alexander, thanks for your answers. I finally figured it out with the computer program and scientific calculator. :)