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.
Phospholipids like lecithin is used as raw material. The phospholipid molecules have heads that love water. They also have two tails that are essential fatty acid chains repelled by water. When the phospholipids are put in a solution that is water-based, the heads end up side by side with the tails trailing behind. The fact that the tails repel water means that another layer lines up with the tails facing the tails of the first layer. This natural alignment results in two rows of tightly fitting molecules. These layers form membranes around and inside all cells.
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.
Different methods are known to have certain weaknesses and strengths. Some allow for high load dosing and others offer much lower dose loading. Some of them offer more consistency and stability. The encapsulated content is affected more by some methods than others.
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.
One of the greatest benefits of liposomes is there flexibility. They can be adapted in many different ways to suit different applications. Size, surface charge and lipid content can all be varied according to the techniques used. Conventional methods are effective but much experimentation is still being done. The future holds many new possibilities with the exciting developments taking place in this field.
Phospholipids like lecithin is used as raw material. The phospholipid molecules have heads that love water. They also have two tails that are essential fatty acid chains repelled by water. When the phospholipids are put in a solution that is water-based, the heads end up side by side with the tails trailing behind. The fact that the tails repel water means that another layer lines up with the tails facing the tails of the first layer. This natural alignment results in two rows of tightly fitting molecules. These layers form membranes around and inside all cells.
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.
Different methods are known to have certain weaknesses and strengths. Some allow for high load dosing and others offer much lower dose loading. Some of them offer more consistency and stability. The encapsulated content is affected more by some methods than others.
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.
One of the greatest benefits of liposomes is there flexibility. They can be adapted in many different ways to suit different applications. Size, surface charge and lipid content can all be varied according to the techniques used. Conventional methods are effective but much experimentation is still being done. The future holds many new possibilities with the exciting developments taking place in this field.
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