Open, microfluidic flow cell for studies of interfacial processes at gas-liquid interfaces

Area of Science:

• Biophysics
• Surface Chemistry
• Biochemistry

Background:

• Interfacial processes involving peripheral proteins are influenced by lipid composition and packing density.
• Lipid monolayers at the gas-liquid interface serve as a model for biological membranes, allowing independent control of these parameters.
• Measuring protein adsorption to these monolayers has historically been challenging.

Purpose of the Study:

• To develop and validate a novel microfluidic flow cell for studying interfacial processes.
• To enable precise control and monitoring of lipid monolayer properties and aqueous-phase composition.
• To characterize the adsorption/desorption kinetics and thermodynamics of glucagon to lipid monolayers.

Main Methods:

• Development of an open, microfluidic flow cell for controlled lipid monolayer studies.
• Implementation of a fluorescence-based method to monitor protein adsorption/desorption.
• Characterization of glucagon adsorption to 1,2-dioleoyl-sn-glycerol monolayers at varying packing densities.

Main Results:

• The microfluidic flow cell allowed for controlled and monitored studies of protein adsorption.
• Varying the packing density of 1,2-dioleoyl-sn-glycerol did not affect glucagon adsorption extent.
• Comparable measurements with 1-steaoryl-2-oleoyl-sn-glycero-3-phosphocholine revealed a critical dependence on packing density.

Conclusions:

• The developed microfluidic flow cell provides a versatile platform for interfacial process research.
• The system allows for high control over both lipid monolayer properties and aqueous-phase composition.
• This technology is expected to have broad applicability in studying protein-lipid interactions at interfaces.