Figure 4.

Simplified version of the experimental set-up used. The microporous ultrafiltration membrane (diameter of approximately 9 mm) with the polymerized lipid film was placed between the two plastic layers of the Saran-Wrap, with the filter centered on a 0.32 mm orifice. The Saran-Wrap is clamped between two Perspex blocks and extends their limits, so no leakage of the electrolyte solution will occur around the edges of the blocks. Stirring can be made with a magnetic flea in a small well. (Reprinted from ref. [40] with permission).