Freeze-Dried Liposome Formulation for Small Molecules, Nucleic Acid, and Protein Delivery

Liposomes are one of the means in the drug delivery system that is quite promising because of its ability to carry active ingredients, both hydrophilic and lipophilic. In addition, the structure of lipid bilayers that resemble cell bilayer membranes is useful in optimizing liposomes' ability through increased internalization of active ingredients into cells. However, liposomes themselves are physically and chemically vulnerable systems, so increasing liposome stability is one of the primary considerations in liposome formulations. Lyophilization or freeze-drying can increase the shelf-life of liposomes, but the process itself is very extreme and prone to triggering damage to vesicle structures. Lyoprotectans from sugars and polyols are usually employed to improve the formulations' stability during the drying process. Physical characterization of the liposome end product is done by looking at the system's morphological appearance, crystallinity profile, thermal analysis, and functional group analysis.