Supramolecular assemblies of lipid-coated polyelectrolytes

Area of Science:

• Supramolecular chemistry
• Materials science
• Biotechnology

Background:

• Lipid-nucleic acid complexes are known supramolecular assemblies.
• The self-assembly of diverse polyelectrolytes coated with lipids remains underexplored.
• Understanding nanoscale organization is crucial for applications like gene delivery.

Purpose of the Study:

• To reveal a general class of supramolecular assemblies formed by lipid-coated polyelectrolytes.
• To investigate the nanoscale internal organization of these assemblies using various synthetic and biological polyelectrolytes.
• To explore the relationship between polyelectrolyte properties (length, rigidity) and assembly morphology.

Main Methods:

• High-resolution cryo-electron microscopy (cryo-EM) for visualizing nanoscale organization.
• Coarse-grained modeling to simulate self-assembly of lipid-coated polyelectrolytes.
• Investigation of poly(styrene sulfonic acid), carboxylmethylcellulose, and filamentous actin.

Main Results:

• Identified a general class of supramolecular assemblies from diverse lipid-coated polyelectrolytes.
• Cryo-EM revealed consistent nanoscale internal organization across different polyelectrolytes.
• Modeling showed morphology depends on polyelectrolyte length and rigidity, matching experimental data.
• Increased polyelectrolyte rigidity extended the correlation range of the order parameter.
• Electrostatic interactions stabilize finite-size equilibrium assemblies.

Conclusions:

• Lipid-coated polyelectrolytes form a versatile class of supramolecular assemblies.
• Assembly morphology is tunable via polyelectrolyte length and rigidity.
• These assemblies offer a generic platform for interfacing polyelectrolytes with cells, potentially for gene delivery.