Robust reagent addition and perfusion strategies for droplet-interface bilayers.

We have designed two novel devices which extend the applications for the droplet-interface bilayer (DIB) as a model membrane system. The add-chip allows successive reagent additions to one side of the lipid bilayer during an experiment while maintaining a simple setup with much lower volumes than in planar bilayer systems. The flow-chip is capable of multiple complete solution perfusions concurrently with electrophysiology measurements. Both devices preserve all of the key advantages that DIBs have relative to planar membranes, including low volume, leaflet asymmetry and the ability to separate the monolayers prior to further analysis of a droplet's contents. As a demonstration, we use these devices to monitor and quantitate molecular transport across DIBs.