Liposomal stabilization using a sugar-based, PEGylated amphiphilic macromolecule

• The amphiphilic macromolecule (AM) prevents DPPC-based liposomes from aggregating.
• AM reduces leakage from DPPC-based liposomes in a concentration-dependent manner.
• AM reduces in vitro uptake of DPPC-based liposomes by macrophages.

Liposomes are an important class of colloidal drug delivery systems, yet the clinical applications of conventional liposomes can be hampered by poor colloidal and biological stabilities. In this work, a sugar-based, PEGylated amphiphilic macromolecule (AM) was evaluated for its ability to stabilize dipalmitoyl phosphatidylcholine (DPPC)-based liposomes. Compared to unmodified liposomes, AM-stabilized liposomes exhibited enhanced colloidal stability, maintaining relatively constant particle sizes for 5 weeks without aggregation. AM-stabilized liposomes also showed significantly decreased membrane permeability, even in the presence of serum. Finally, AM-stabilized liposomes displayed improved biological stability, significantly inhibiting phagocytosis by macrophages. Overall, the effectiveness of AM to stabilize liposomes was comparable to a conventional stabilizing agent, PEG-modified phosphatidylethanolamine. Based upon these results, AM is a promising stabilizing agent for colloidal drug delivery applications and currently being optimized.

Figure optionsDownload high-quality image (63 K)Download as PowerPoint slide