Liposome excipients, as an important part of the drug delivery system, have attracted much attention in the field of drug formulation in recent years. They can improve the solubility, stability, and bioavailability of drugs, thus enhancing their therapeutic effects. In this paper, we will introduce several common liposome excipients, including phospholipids, cholesterol, surfactants, and other new excipients, and discuss their applications in drug formulation.
Phospholipid excipients are among the most commonly used excipients in liposomes. They are primarily made of glycerophospholipids and possess good biocompatibility and biodegradability. Phospholipid excipients can form stable liposome structures and offer suitable carriers for drugs. Common phospholipid excipients include lecithin and phosphatidylserine. These excipients can significantly enhance the encapsulation rate and stability of the drug while reducing the drug's toxicity in the preparation of liposomal drugs.
Cholesterol excipients play an important role in liposome preparation. Cholesterol can regulate the fluidity and stability of the liposome membrane, thus enhancing the encapsulation ability and stability of liposomes with respect to drugs. Additionally, cholesterol can interact with phospholipids to form a tighter liposome structure, which aids in preventing drug leakage during the delivery process. Therefore, the appropriate amount of cholesterol excipients in the preparation of liposomal drugs can optimize the performance of liposomes and improve the therapeutic effect of drugs.
Surfactant excipients are mainly used to regulate the size, morphology, and surface properties of liposomes in liposome preparation. These excipients usually possess hydrophilic and hydrophobic ends, can form a stable interfacial layer on the surface of the liposome membrane, and prevent the aggregation and fusion of liposomes. Simultaneously, surfactant excipients can also improve the compatibility of liposomes with biological fluids and enhance the bioavailability of drugs. Common surfactant excipients include polyethylene glycol (PEG)-modified phospholipids, tween, and others.
In addition to the above common liposome excipients, many new excipients have emerged in recent years, such as polymers, sugars, and others. These new excipients possess unique properties and functions, providing more possibilities for the preparation and application of liposomal drugs. For instance, polymer excipients can enhance the mechanical strength and stability of liposomes and increase the circulation time of drugs in the body; sugar excipients can improve the hydrophilicity of liposomes and enhance the water solubility of drugs. The research and application of these new excipients have injected new vitality into the development of liposomal drug formulations.
In conclusion, different kinds of liposome excipients play their own unique roles in drug formulations. Phospholipid, cholesterol, and surfactant excipients are commonly used in liposome drug preparation, which can optimise the structure and properties of liposomes and improve the therapeutic effect of drugs. The research and application of new excipients provide more possibilities for the development of liposome drug preparation. In the future, with the continuous progress of science and technology and the in-depth development of the field of drug formulation, we expect to see more innovative liposome excipients, which will make a greater contribution to the cause of human health.
