Freeze-dried Liposomal Systems
The main reason for freeze drying (lyophilization) of the liposomes is to improve the storage stability by preventing the hydrolysis of the phospholipids and by slowing down the degradation of the liposomal system in the absence of water molecules.
Unfortunately the liposomal structure may also be damaged by freeze drying process unless lyoprotectants such as disaccharides (sucrose, lactose and trehalose) are used.
Freeze drying without using a lyoprotectant results in fusion and aggregation of liposomes and extensive leakage of the encapsulated water soluble compounds upon hydration. However if the goal is to make multilamellar vesicles (MLVs) or the encapsulated drug is hydrophobic and interacts with the lipid membrane then freeze drying the liposome without the lyoprotectants may be an attractive option however most of the time using a lyoprotectant is necessary.
Encapsula provides various custom-made formulations of freeze-dried liposomes for R&D laboratories. For more information send us an email at info@encapsula.com
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