The human body is a marvel of information technology: instructions are constantly exchanged within and between cells. To ensure that the individual signals are not lost in a general noise, life is based on two important principles: Our body is divided into smaller, protected units and the exchange of information between these units is strictly regulated.
We commonly know the subunits of our body as cells and organs. Together they form a whole, but each unit is self-contained. The cell membrane plays a central role in this.
The cell membrane is a layer of special fat, sugar and protein molecules. An important aim of the cell membrane is to clearly separate the inside of the cell from its external environment and to enable an orderly exchange of molecules through the cell membrane.
Information is often exchanged in the human body in the form of highly sensitive molecules. These molecules must be specially protected so that they are not destroyed in the chemically reactive environment of the human bloodstream. Protection is achieved by packaging the information molecules in a special container: liposomes.
Liposomes are nanometer-sized “fat globules” that float in water and are also filled with water inside. Similar to a water balloon, for example, which floats in water, just incredibly much smaller. Liposomes are also not as fragile as water balloons and, once formed, can remain stable for years.
Liposomes can also be produced quite simply outside the body by mixing fat-like molecules (so-called phospholipids) with water. As fat and water repel each other, the fat-like molecules come together to form a ball, a liposome. Just like natural liposomes, the inside of artificial liposomes also consists of water.
Other molecules, such as active pharmaceutical ingredients, can also be packaged in the liposomes. This has the great advantage that the medication is no longer dissolved directly in an infusion bag, but is protected in a liposome. When the liposomes are injected into a patient's bloodstream, the liposomes act as envelopes: Addressed to a specific location in the body, the liposomes are transported through the bloodstream and deposited in a tumor, for example. There the liposomes open and the drug, in this example a cancer drug, is released. This ensures that toxic active substances do not circulate freely in the bloodstream, but are always protected in liposomes before reaching their destination. As a result, liposomal cancer drugs have far fewer side effects than standard drugs, and the distribution of the active ingredient in the body (known as biodistribution) is massively influenced by the liposome system. Hair loss, for example, is one of the common side effects of chemotherapy and hardly ever occurs with liposomal therapies.
In summary, it can be said that liposomes are packages that have been copied from nature. They make it possible to transport and release drugs efficiently and in a targeted manner in the human body.
