Hierarchical Structural Organization in Bioinspired Peptide Coacervate Microdroplets

Area of Science:

• Biophysics
• Materials Science
• Chemical Biology

Background:

• Peptide coacervates are biomolecular condensates with potential applications in drug delivery and biomaterials.
• Understanding their hierarchical structure and dynamics is crucial for controlling their properties.
• Previous studies lacked atomic-scale resolution of interactions within intact coacervate droplets.

Purpose of the Study:

• To explore the dynamic and hierarchical structural organization of peptide coacervate microdroplets.
• To apply Transferred Nuclear Overhauser Effect Spectroscopy (TrNOESY) to peptide coacervates for residue-level interaction analysis.
• To elucidate the mechanisms of self-association and cargo sequestration within these droplets.

Main Methods:

• Transferred Nuclear Overhauser Effect Spectroscopy (TrNOESY) for residue-level interaction detection.
• Small-angle neutron scattering (SANS) with selective deuteration for structural analysis.
• Confocal microscopy for visualization of droplet organization.

Main Results:

• Direct, high-resolution detection of residue-level interactions within intact peptide coacervate droplets.
• Identification of dynamic interactions driving peptide cluster self-association.
• Observation of a porous network structure within droplets formed by self-associated peptide clusters.
• Demonstration of size-selective cargo sequestration facilitated by the porous network.

Conclusions:

• Peptide coacervates exhibit dynamic, hierarchical structural organization from meso- to atomic scales.
• TrNOESY is a powerful technique for studying interactions in native coacervate systems.
• The porous network structure plays a key role in the functional properties of peptide coacervates, such as cargo encapsulation.