Lipid system is an artificial cell membrane, which has an onion-like closed spherical structure. It can protect the drug in its structure and exert a targeted effect.
It is especially suitable as an anticancer drug carrier to improve the therapeutic efficacy of drugs and reduce toxicity, side effects etc.
Liposomes are composed of phospholipids as skeleton membrane and additives. Phospholipids used to prepare liposomes are divided to natural phospholipids and synthetic phospholipids.
AVT is specialized in drug delivery systems such as liposomes, lipid emulsions, and micro-nano targeted formulations. Our products cover natural phospholipids, synthetic phospholipids, functionalized phospholipids, nucleic acid delivery and other sub-fields.
Among liposome excipients, there are many kinds of phospholipids.
Synthetic phospholipids are preferred excipients with characteristics of stable properties, anti-oxidation, and stabilizing the finished products.
Utilizing mixed phospholipids and cholesterol with different phase transition temperatures can increase stability.
The liposome preparation using sucrose as a freeze-drying protective agent has good stability and reconstitution effect after reconstitution.
Studies have shown that the lyophilized liposome with 10% trehalose as the protective agent has the smallest particle size changes and the best protective efficacy.
Utilizing sucrose octasulfate potassium salt as drug delivery vehicle has improved the in vivo behaviors such as drug therapeutic index, bioavailability, release as well as plasma concentration-time curve.
Synthetic and semi-synthetic phospholipids are not easily oxidized compared with natural phospholipids. They have fixed composition and clear phase transition temperature. Thus, they are more applicable in research and production. Dipalmitoyl phosphatidyl choline (DPPC), dioleoyl phosphatidyl choline (DPPC), dioleoyl phosphatidyl choline Alkali (DOPC), etc., are the most widely used liposome skeleton membrane materials.
Cholesterol can regulate the fluidity of phospholipid bilayer membrane, reduce membrane permeability and reduce drug leakage. In the meantime, the lipid membrane can maintain a certain flexibility and enhance the ability of liposome vesicles to resist changes in external conditions. It has a certain protective effect on the oxidation of phospholipids. Cholesterol has a biphasic regulatory effect on the phase transition of phospholipids.
In the freeze-drying process of liposomes, sucrose and trehalose are the two mostly used protective agents. Sucrose can reduce membrane fusion, protect the liposome particles from breaking and leaking drugs during the freeze-drying process, and adjust the osmotic pressure at the same time. In addition, it can also act as an excipient—it can affect the shape, porosity, and collapse of the freeze-dried product. The liposome preparation using sucrose as the lyoprotectant after reconstitution has good stability and reconstitution effect.
Utilizing sucrose octasulfate potassium salt as drug delivery vehicle can improve the in vivo behaviors such as drug therapeutic index, bioavailability, release as well as plasma concentration-time curve. Threfore, irinotecan liposome Onivyde® uses sucrose octasulfate for gradient drug loading.
1. Phospholipid products are used as liposome skeleton membrane materials.
2. Cholesterol cannot form liposomes alone, it needs to form bimolecular membranes together with phospholipids.
If you have any questions, please don't hesitate to contact us. We're always here to help with Pharmaceutical Excipients for your business. We can provide products ranging from grams to tons. AVT is able to produce and even register the product in US FDA according to your special needs.