Control of membrane permeability in air-stable droplet interface bilayers

Area of Science:

• Biophysics
• Materials Science
• Synthetic Biology

Background:

• Air-stable droplet interface bilayers (airDIBs) are promising for biosensing but suffer from limited lifetimes due to evaporation.
• Evaporation-induced destabilization reduces the operational window for airDIBs compared to traditional submerged DIBs.

Purpose of the Study:

• To investigate methods for extending the operational lifetime of airDIBs.
• To understand the impact of temperature and humidity on airDIB stability and membrane properties.

Main Methods:

• Controlled manipulation of temperature and relative humidity around airDIBs.
• Monitoring airDIB stability and electrical resistance over time.
• Investigating lipid bilayer phase transitions induced by dehydration.

Main Results:

• AirDIB lifetimes were extended by up to an order of magnitude by maintaining temperature just above the dew point.
• Raising temperature above the dew point induced lipid bilayer dehydration, increasing membrane disorder and permeability.
• Bilayer electrical resistance was significantly affected by temperature-induced dehydration and disorder.

Conclusions:

• Temperature and relative humidity are critical, tunable parameters for controlling airDIB stability and composition.
• Maintaining optimal environmental conditions near the dew point can dramatically improve airDIB performance for ambient biosensing applications.
• Understanding dehydration transitions is key to designing robust airDIB systems.