Liposomes are microscopic spheres made from the same material as the cell membranes in the human body. They have attracted a lot of attention due to their amazing properties. They can be used to carry drugs, nutrients and other agents to specific destinations in the body. There are various different preparation methods and techniques for liposome manufacturing and those used depend on on various factors.
When phosphlipids such as lecithin come into contact with water, an interesting effect occurs. The molecules consist of a head which loves water and two tails that repel it. This means that the heads all face one side and the tails the other. Another layer is formed with tails all facing the tails of the first later and the heads facing the other way. These layers form the membranes around and inside every cell of the human body.
It is possible to customize liposomes for different applications. These applications include delivering drugs to kill cancer cells, transferring DNA to make genetic modifications to cells or delivering cosmetic nutrients to the skin. Preparation method is affected by the application. For example, the concentration and toxicity of drugs used for treating cancer requires a particular preparation method.
The tiny size of liposomes means they are quickly assimilated into the bloodstream for delivery throughout the body. The payload is biologically inert until it is delivered to needy cells. They are all basically the same but the differences between them occur in the way they are released, how long this takes as well as where and why this occurs.
Liposomes are usually synthesized by mixing and dissolving phospholipids in organic solvent. A clear lipid film is formed by removing the solvent. Hydration of this film eventually leads to formation of large vesicles which have several layers, much like the structure of an onion. Each bilayer is separated from the other by water. A form of energy is required to reduce their size. Sonication, agitation by sound waves, is one method used and extrusion is another.
Liposomes are actually fairly simple to make, not requiring complex materials, equipment or methods. Each method and technique offers certain benefits and has some failings. Sonication can cause structural changes to what is entrapped. Liquid hydration methods do not produce a high payload.
Some of the problems that have to be faced are structural instability, inconsistency in size and expensive production costs. Liposomal delivery systems are still in the experimental stage. The precise ways in which they act within the body are being carefully studied as well as ways in which they can be made to target diseased tissue or a specific organ.
Although conventional methods of manufacture are effective, research continues apace to make them more so. Much research is being conducted into ways in which liposomes can be created that have a strong chemical affinity for the cells of a particular organ or kind of tissue. They also need to have the ability to deliver payloads to the cells as efficiently as possible.
When phosphlipids such as lecithin come into contact with water, an interesting effect occurs. The molecules consist of a head which loves water and two tails that repel it. This means that the heads all face one side and the tails the other. Another layer is formed with tails all facing the tails of the first later and the heads facing the other way. These layers form the membranes around and inside every cell of the human body.
It is possible to customize liposomes for different applications. These applications include delivering drugs to kill cancer cells, transferring DNA to make genetic modifications to cells or delivering cosmetic nutrients to the skin. Preparation method is affected by the application. For example, the concentration and toxicity of drugs used for treating cancer requires a particular preparation method.
The tiny size of liposomes means they are quickly assimilated into the bloodstream for delivery throughout the body. The payload is biologically inert until it is delivered to needy cells. They are all basically the same but the differences between them occur in the way they are released, how long this takes as well as where and why this occurs.
Liposomes are usually synthesized by mixing and dissolving phospholipids in organic solvent. A clear lipid film is formed by removing the solvent. Hydration of this film eventually leads to formation of large vesicles which have several layers, much like the structure of an onion. Each bilayer is separated from the other by water. A form of energy is required to reduce their size. Sonication, agitation by sound waves, is one method used and extrusion is another.
Liposomes are actually fairly simple to make, not requiring complex materials, equipment or methods. Each method and technique offers certain benefits and has some failings. Sonication can cause structural changes to what is entrapped. Liquid hydration methods do not produce a high payload.
Some of the problems that have to be faced are structural instability, inconsistency in size and expensive production costs. Liposomal delivery systems are still in the experimental stage. The precise ways in which they act within the body are being carefully studied as well as ways in which they can be made to target diseased tissue or a specific organ.
Although conventional methods of manufacture are effective, research continues apace to make them more so. Much research is being conducted into ways in which liposomes can be created that have a strong chemical affinity for the cells of a particular organ or kind of tissue. They also need to have the ability to deliver payloads to the cells as efficiently as possible.
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