The suspension of liposomes is then transferred to the top of a size-exclusion column without disturbing the stationary phase. The column should be pre-eluted with the NaNO3 solution. A small volume of eluent is used to rinse the extrusion kit and to transfer all remaining liposomes to the column. The liposomes elute first and give the drops a cloudy appearance, well observable against a dark background (Figure ). The liposomes can be collected into a volumetric flask or measuring cylinder for the final dilution. The collection should be stopped as soon as the drops do not have a cloudy appearance anymore to avoid contamination with the unencapsulated lucigenin. Shortly after this, the unencapsulated lucigenin is eluted as a yellow solution (Figure ).