Liposomes are spherical artificial vesicles composed of one or more lipid bilayers organized around an internal aqueous core, with the polar head groups oriented to the inner and outer aqueous phase. This organized structure offers to liposomes the unique ability to load and deliver molecules with different solubility. The size of liposomes ranges from 30 nm to several micrometers. Due to their size, biocompatibility, biodegradability, low toxicity, and ability to simultaneously encapsulate hydrophilic and hydrophobic bioactive compounds, liposomes are utilized to increase stability, solubility, bioaccessibility, and/or bioavailability of bioactive compounds, and to provide targeted delivery and controlled release in food, pharmaceutical, and cosmetic industries.
Liposomes as a drug delivery system can be used to improve therapies for a range of biomedical applications by stabilizing therapeutic compounds, overcoming obstacles to cellular and tissue uptake, and improving biodistribution of compounds to target sites in vivo. The ability of liposomes to deliver drugs can be affected by the number and rigidity of lipid bilayers, size, surface charge, lipid organization, and surface modification. The drug loaded into liposome is protected against physiologically occurring events, such as enzymatic degradation, chemical and immunologic inactivation, and fast plasma clearance, contributing to improve and extension of its action. In addition, the drug in the liposome minimizes the exposure to healthy tissue, reducing undesirable adverse side effects compared to free drugs.
The main component of liposomes is glycerophospholipids, which are amphiphilic lipids composed of a glycerol molecule bound to a phosphate group and to two fatty acid chains that may be saturated or unsaturated. The selection of phospholipids, head group and chain length, as well as the ratio of liposomes components are crucial features to determine safety, stability, and efficiency of liposomes. Amerigo Scientific offers a wide range of liposomes of different components, modified liposomes, and other liposome research tools to meet the needs of drug delivery and other scientific research applications.