Supplementary Material for "Entropic barrier of water permeation through single-file channels"

Python code for a global activation energy (E_a) fit to temperature dependent stopped-flow data (*.bka file):

As shown in our manuscript, the accuracy of E_a estimation from stopped-flow data is greatly increased by a global fit to the data. Thereby, the ensemble of curves of a sample at different temperatures is fitted globally using the analytical solution (Eqn. 10), instead of evaluating permeabilities for different temperatures individually and independently. In our python code, osmotic water flux measurements of a sample (mixture of vesicles with and without water channels) recorded at different temperatures are simultaneously fitted using Eqn. 7, Eqn. 10, Eqn. 11 and Eqn. 14. Here, the only free fit parameter, which is evaluated for the different temperatures independently is coefficient b from Eqn. 7. The accuracy of the results increases with the span of the temperature values, number of performed measurements and a decreased empty vesicle fraction.