Product Information

I. Traditional Liposome Stage

1. Origin and Early Exploration (1960s - 1970s)

Liposomes were first discovered by the British hematologist Alec D. Bangham in 1965. When studying the dispersion behavior of phospholipids in water, he observed that phospholipid molecules spontaneously formed multi - layer vesicle structures similar to those of biological membranes. At that time, the research mainly focused on basic physical chemistry and biological membrane simulation.
Researchers began to realize that liposomes could encapsulate both water - soluble and lipid - soluble substances, providing a potential carrier for drug delivery. For example, in the laboratory, simple drug model molecules such as fluorescent dyes were encapsulated in liposomes to observe their encapsulation and release characteristics.

2. Initial Application Attempts (1970s - 1980s)

With a further understanding of the structure and properties of liposomes, their applications in the medical field began to be explored. This period mainly focused on the delivery of anti - tumor drugs.
For example, some chemotherapeutic drugs such as doxorubicin were encapsulated in liposomes, attempting to change the pharmacokinetics and tissue distribution of the drugs through the encapsulation of liposomes, and reduce the toxicity of the drugs to normal tissues. However, early liposomes had problems such as poor stability and being easily cleared by the mononuclear - phagocyte system (MPS). They had a short circulation time in the body and were cleared by the immune system before they could fully exert their efficacy, which greatly limited their clinical applications.

II. Long - Circulating Liposome Stage

1. Emergence of PEG - Modified Liposomes (1980s - 1990s)

To overcome the problem of short circulation time of traditional liposomes in the body, scientists introduced the technology of polyethylene glycol (PEG) - modified liposomes. PEG is a hydrophilic polymer. When it is attached to the surface of liposomes, it can form a hydrated film around the liposomes.
This hydrated film can reduce the interaction between liposomes and plasma proteins, thereby reducing the recognition and uptake of liposomes by the mononuclear - phagocyte system. For example, Doxil, the world's first marketed long - circulating liposomal drug, is a PEG - modified liposome encapsulating doxorubicin. The emergence of Doxil greatly extended the circulation time of liposomes in the blood, enabling the drugs to have more opportunities to reach tumor tissues and improving the therapeutic effect of the drugs.

2. Optimization and Diversification (1990s - early 2000s)

Researchers conducted in - depth studies on PEG - modified liposomes, including the optimization of the molecular weight of PEG, the connection method, and the composition of liposomes.
At the same time, the application scope of long - circulating liposomes expanded from anti - tumor drugs to other fields, such as the delivery of anti - inflammatory drugs and antibiotics. For example, in the treatment of some chronic inflammatory diseases, long - circulating liposomes encapsulating anti - inflammatory drugs can make the drugs accumulate better at the inflammatory sites, increase the local drug concentration, and reduce systemic side effects.

III. Targeted Liposome Stage

1. Antibody - Liposome Conjugation Technology (Early 2000s - Present)

To further improve the therapeutic effect of liposomes and enable them to deliver drugs more precisely to diseased cells, the technology of targeted liposomes emerged. Among them, conjugating antibodies to the surface of liposomes is an important strategy.
For example, by connecting antibodies against specific antigens on the surface of tumor cells to the surface of liposomes, the liposomes can accurately recognize and bind to tumor cells like "missiles". This targeted liposome can increase the uptake of drugs in tumor cells and reduce their distribution in normal tissues. It has been applied in the treatment research of various cancers such as breast cancer and lung cancer.

2. Ligand - Liposome Targeting System (Early 2000s - Present)

In addition to antibodies, other ligands can also be used to achieve the targeting of liposomes. For example, some small molecule ligands such as folic acid and transferrin can be utilized. The folic acid receptor is overexpressed on the surface of many tumor cells, while it is expressed at a relatively low level on the surface of normal cells.
Therefore, by connecting folic acid to the surface of liposomes to deliver drugs, the liposomes can preferentially bind to tumor cells. This ligand - liposome targeting system has advantages such as relatively low cost and easy preparation, and has also been widely applied in the treatment research of tumors and some other diseases (such as brain diseases, using transferrin to target the receptors of the blood - brain barrier).

IV. Smart Liposome Stage (Emerging Stage)

1. Environment - Responsive Liposomes (Last 10 - 15 years)

Smart liposomes can change their structure and properties according to changes in the surrounding environment, such as pH, temperature, and enzyme concentration. In the tumor microenvironment, the pH is usually lower than that in normal tissues. pH - responsive liposomes can take advantage of this feature.
For example, a pH - sensitive liposome can be designed to remain stable under normal physiological pH conditions. When it reaches the acidic microenvironment of the tumor, the structure of the liposome changes, such as an increase in membrane permeability, thereby rapidly releasing the drug. This type of environment - responsive liposome can improve the drug release efficiency at the lesion site and further enhance the therapeutic effect.

2. Multifunctional Liposomes (Last 10 - 15 years)

Multifunctional liposomes combine multiple functions such as long - circulation, targeting, and environment - responsiveness. For example, a liposome can simultaneously have PEG modification to extend the circulation time, antibodies to target tumor cells, and a pH - sensitive drug release mechanism.
The design concept of this multifunctional liposome is to maximize the accuracy and effectiveness of drug delivery. It has great application potential in complex disease treatment scenarios, such as combined tumor therapy or multi - target therapy.

Natural Field co-loaded liposomes belong to the innovative technology of smart liposomes, using ginsenosides instead of cholesterol as a new type of carrier, which can achieve higher bioavailability