Can I measure what proportion of cells are responsive in my calcium flux assay?

Yes, the proportion of cells which are responsive in calcium flux assays is able to be measured. In one study, individual profiles depicting the kinetics of calcium responsiveness were generated by plotting fluorescence intensity against time in seconds. Researchers calculated the proportion of maximally responsive cells by dividing the number of cells exhibiting a rapid and sustained flux profile  by the total number of cells in the observed field. Additionally, the researchers determined the calcium EC50 values by plotting the proportion of maximally responsive cells as a function of the logarithm of calcium concentration. This approach allowed them to quantify the sensitivity of cells to varying levels of calcium.