Lyophilized liposomes product series are freeze-dried liposomes with various types of lipids and wide range of zeta potentials and different properties. These products should be used by scientists who understand liposome formulation and have the proper equipment to check the size, separate non-encapsulated drugs and do the proper assays.
Liposomes are extensively used to study the interaction of proteins, peptides and other molecules with the surface of a lipid membrane. One of the parameters that affects this interaction is the charge of the liposomal membrane. Liposomes are always made in aqueous environment and they are sized to the desired size in liquid state using various methods such as high-pressure extrusion through nano sized pore track etch membranes. In rare occasions, liposomes are freeze dried and proliposomes are formed in the presence of a lyoprotectant such as trehalose. Using a lyoprotectant is necessary in order to maintain the size of the liposomes after rehydration.
Natural Phosphatidylserine (PS) extract liposomes products are composed of four liposomes made from phosphatidylserine (PS) lipids that are made from natural lipids that are extracted from either brain or soybean. Adding 30% cholesterol makes the liposomes serum stable and is necessary when the liposomes are used in the presence of serum.
These liposomes are all anionic due to the negative charge of phosphatidylserine.
Brain phosphatidylserine (PS) is composed of both saturated and unsaturated lipids. Brain PS contains much larger percentage of saturated lipids compare to Soy PS. Brain PS is mainly composed of four lipids: 42% of 18:0 lipid, 30% of 18:1 lipid, 2% of 20:4 lipid and 11% of 22:6 lipid.
Soy PS is composed of both saturated and unsaturated lipids. Soy PS contains more unsaturated lipids. Soy PC is mainly composed of 5 lipids: 10% of 16:0 lipid, 3% of 18:0 lipid, 12% of 18:1 lipid, 68% of 18:2 lipid, and 7% of 18:3 lipid.