High throughput onion-like liposome formation with efficient protein encapsulation under flash antisolvent mixing

Area of Science:

• Biotechnology
• Materials Science
• Nanotechnology

Background:

• Encapsulating proteins in lecithin-based liposomes presents significant challenges in efficiency and capacity.
• Defective liposome bilayers can lead to fusion and instability, hindering protein loading.

Purpose of the Study:

• To develop a scalable method for producing liposomes with enhanced protein encapsulation efficiency.
• To investigate the role of cholesterol in stabilizing lecithin liposomes and improving protein loading.

Main Methods:

• Utilized Flash Nano-Precipitation (FNP) for rapid liposome formation.
• Employed Quartz Crystal Microbalance with Dissipation (QCM-D) and Cryo-Transmission Electron Microscopy (Cryo-TEM) for structural and adsorption analysis.
• Investigated Bovine Serum Albumin (BSA) encapsulation in lecithin and lecithin-cholesterol liposomes.

Main Results:

• FNP produced small, uniform liposomes with high batch repeatability.
• Incorporating cholesterol (lecithin:cholesterol ratio of 5:3) created compact bilayers, preventing liposome fusion.
• Achieved high BSA encapsulation efficiency (~68%) and loading capacity (~6%) in lecithin-cholesterol liposomes.

Conclusions:

• Cholesterol addition stabilizes lecithin liposomes, enabling efficient protein encapsulation via FNP.
• Rapid adsorption between BSA and lecithin bilayers drives layer-by-layer assembly for compact liposome structures.
• FNP offers a scalable manufacturing approach for protein-loaded liposomes, with potential applications in drug delivery and biomaterials.