FTIR Imaging as a Tool for Studying Protein Dynamics and Interactions at the Oil/Water Interface with Spatial...

Area of Science:

• Food Science
• Materials Science
• Biophysics

Background:

• Emulsions are crucial in food, pharma, and cosmetics, requiring optimized structures and functions.
• Characterizing molecular interactions at emulsion interfaces is vital for stability and performance.
• Understanding protein adsorption and conformational changes is key for protein-stabilized emulsions.

Purpose of the Study:

• To chemically map single emulsion droplet interfaces in situ using Fourier-transform infrared (FTIR) imaging.
• To investigate the impact of processing conditions on protein structure and distribution at the oil/water interface.
• To evaluate conformational changes in bovine serum albumin (BSA) stabilized emulsions.

Main Methods:

• Utilized a microfluidic platform to generate single emulsion droplets stabilized by BSA.
• Employed Fourier-transform infrared (FTIR) imaging for non-destructive chemical mapping of droplet interfaces.
• Analyzed the amide I band to assess protein secondary structure and spatial distribution.

Main Results:

• FTIR imaging successfully distinguished protein-rich and oil phases within emulsion droplets.
• Distinct protein zones with varying structural motifs and concentrations were identified around the droplets.
• Processing conditions significantly influenced the secondary structure and spatial distribution of BSA at the interface.

Conclusions:

• FTIR imaging is a powerful tool for investigating emulsion interfaces and tracking protein structural changes.
• Processing history profoundly impacts protein structure and distribution at the oil/water interface.
• Findings provide insights for designing protein-stabilized emulsions with tailored functional properties.