Where y is the Cl -or F -efflux (%) normalised against the 100% anion efflux value, y0 is the offset of the fitted non-linear curve to the experimental data, A1 and A2 are the first and second amplitude constants, respectively, x is time t, and t1 and t2 are the first and second time constants, respectively, which are derived during the data fitting process. The generated amplitude (A1 and A2) and time (t1 and t2) constants are then used to find the kini rate constant using Equation :