Asymmetric Liposomes Production

Creative Biostructure makes every effort to perfect the liposome preparation service. With combined experience in liposome production and drug delivery, we have developed a series of protocols and techniques for asymmetric liposome production, aiming to deliver drug carriers with enhanced biocompatibility and efficacy.

How asymmetric liposome works.

Asymmetric liposomes have different lipids in outer and inner leaflets, which would greatly increase the flexibility of vesicle in drug delivery systems. It has been well known that the phospholipid distribution in natural membranes is asymmetric. For example, phosphatidyl tcholine and sphingomyelin concentrate at the outer leaflet whereas phosphatidylethanolamine, phosphatidylinositol and phosphatidylserine are mainly localized in the inner leaflet. Typically, Lipids are self-assembled symmetrically in artificial liposomes regardless of the preparation methods. As drug delivery carriers, asymmetric liposomes with advanced functions are appealing candidates for targeted accumulation and controlled drug release. Their outer and inner leaflet could be manipulated depending on the nature of encapsulated drug molecules. For example, asymmetric liposomes help deliver negatively charged siRNA to target organs by having positively charged inner layer that encapsulates siRNA with high efficiency, and negatively charged outer surface prevents nonspecific uptake of the asymmetric liposomes. The unique tunability of asymmetric liposomes opens a wide door for multi-site functionalization, resulting in highly engineered liposomes as advanced drug delivery vesicles.

High-throughput X-ray crystallography for fragment based drug design Figure 1. Schematic representation of asymmetric vesicle preparation. (PNAS, 2003)

Asymmetric Liposome Applications

Asymmetric liposomes have enriched chemical and mechanical properties in vivo, and exhibit good loading efficacies for both hydrophobic and hydrophilic drugs, including protein drugs and small molecules. More importantly, its efficient drug loading capacity, fast endocytosis rate and endosomal escape ability are in good compliance with the key requirements for next generation drug delivery.

Creative Biostructure offers a full spectrum of services for asymmetric liposomes:

  • Asymmetric liposomes preparation method development
  • Encapsulation of sensitive or unstable drug molecules, such as calcein and siRNA.
  • Analytical Services: Encapsulation efficiency (EE%), average particle size (PS), polydispersity index (PDI), zeta potential (ZP), liposomal morphology, asymmetry stability, drug release studies, and in vivo evaluation.
  • In vitro drug release study
  • In vivo pharmacokinetic and pharmacodynamics studies

Creative Biostructure offers trusted, rapid yet flexible service plans to meet the specific needs of the clients. For more information, please contact us.

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  1. Yi Zhao, Xiaoming Li, Xiaotian Zhao et al. (2017) Asymmetrical polymer vesicles for drug delivery and other applications. Frontiers in pharmacology. 8: 374.
  2. Ulrich Massing, Sanja Cicko, Vittorio Ziroli. (2008) Dual asymmetric centrifugation (DAC)- A new technique for liposome preparation. Journal of Controlled Release. 125:16-24.
  3. Amir Abbas Mokhtarieh, Sinyoung Cheong, Semi Kim. (2015) Asymmetric liposome particles with highly efficient encapsulation of siRNA and without nonspecific cell penetration suitable for target-specific delivery. Biochimica et Biophysica Acta. 1818: 1633–1641.
For Research Use Only. Not for use in diagnostic or therapeutic procedures.

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