See previous studies:
https://www.ncbi.nlm.nih.gov/pubmed/9512029
https://www.ncbi.nlm.nih.gov/pubmed/11557589
See an example of the anion substitution experiment in the attached file (relative permeability example jmd033017.xlsx).
Find reversal potentials for different anions.
Calculate relative permeabilities using the excel file attached (Relative Permeability jmd033017.xlsx).
Check your understanding of the theory by going through the PDF attached (Anion Substitution Experiment.pdf).