Lysozyme Interaction with Phospholipid Nanodroplets Probed by Sum Frequency Scattering Vibrational Spectroscopy

Area of Science:

• Nanotechnology and Materials Science
• Biophysics
• Surface Chemistry

Background:

• Nanoparticle (NP) interactions in biological systems are dominated by the protein corona.
• Understanding protein corona formation is crucial for NP surface engineering and drug development.
• Molecular mechanisms of interfacial biomolecule action remain largely elusive.

Purpose of the Study:

• To determine the structure and action of biomolecules at interfaces using ultrafast sum frequency scattering (SFS) spectroscopy.
• To investigate biomolecule interactions with 3D nanoscopic interfaces, moving beyond traditional flat models.
• To elucidate the binding and structural changes of proteins within the protein corona.

Main Methods:

• Utilized ultrafast sum frequency scattering (SFS) spectroscopy to analyze 3D lipid monolayers as a model nanocarrier system.
• Applied SFS spectroscopy to study the interaction of lysozyme with lipid monolayers.
• Analyzed SFS spectra in the amide I region and acyl chain order to understand protein binding and lipid layer modification.

Main Results:

• SFS spectra confirmed the presence of lysozyme at the lipid monolayer interface.
• Lysozyme binding induced increased lipid monolayer order and altered acyl chain ordering.
• Changes in lipid headgroup orientation (s-PO2-) indicated lysozyme insertion and disruption of the lipid layer.

Conclusions:

• SFS spectroscopy is effective for interrogating biomolecular interactions at 3D nanoscopic interfaces.
• Lysozyme binding significantly alters the structure and order of lipid nanocarriers.
• This study represents a significant advancement in understanding protein corona formation and biomolecule-interface dynamics.