Composition based strategies for controlling radii in lipid nanotubes

Area of Science:

• Biophysics
• Materials Science
• Chemical Engineering

Background:

• Nature utilizes lipid-bound cells and organelles for nanoscale chemistry.
• Liposome-lipid nanotube networks mimic these cellular environments for chemical studies.
• Controlling nanotube diameter is crucial for these biomimetic systems.

Purpose of the Study:

• To investigate methods for controlling nanotube diameter in liposome-lipid nanotube networks.
• To evaluate the impact of intrinsic membrane curvature on nanotube dimensions.
• To explore lipid composition as a means to tune nanotube diameter.

Main Methods:

• Altering lipid composition of liposome-lipid nanotube networks using two distinct approaches.
• Method 1: Incubation with exogenous lipids – soy phosphatidylcholine (low intrinsic curvature) or soy phosphatidylethanolamine (high intrinsic curvature).
• Method 2: Addition of exogenous lipids during initial liposome formation.

Main Results:

• Addition of soy phosphatidylethanolamine (soy-PE) led to a significant decrease in nanotube diameter.
• Addition of soy phosphatidylcholine (soy-PC) did not result in significant changes to nanotube diameter.
• The observed decrease in nanotube diameter with soy-PE was consistent across both lipid augmentation methods.

Conclusions:

• Soy phosphatidylethanolamine effectively reduces nanotube diameter in liposome networks.
• The effect of soy-PE on nanotube diameter is independent of the method of lipid addition.
• High intrinsic curvature lipids like soy-PE play a key role in facilitating membrane curvature, enabling control over nanotube dimensions.