Applications of liposomes.

Liposomes are the vesicles with a lipid bilayer, and central hydrophilic portion.

They have a wide range of applications in the field of pharmaceutical formulations.

Due the uniform colloidal size from 20nm to 10um prepared from the natural sources thus they are non toxic, biodegradable, and non immunogenic. Due to its outer hydrophilic nature they get easily solubulised in the biological systems and due to their amphiphillic character it can encapsulate both lipidic as well as hydrophilic drug molecules in them.(1)

1. Solubility(1):

Solubility of lipohilic and amphilphilic drugs molecules can be increased by encapsulating in the liposome

Eg: amphotericin-b, minoxidil, porphyrins, anthracyclins

Hydrophallic drugs like- donxorubicin, acyclovir,

2. Targeting: passive targeting of mononuclear phagocytic system like Amphotericin B, porphyrins, antimonials, immunomodulators, also vaccines

3. Sustained release: both in the locally and systemically administered liposomes can show sustained release foe ex: cytarabine, doxorubicin

4. Site specific targeting(2): if the liposomes are surface modified by ligands which can target an specific site in the body, ex: antiinflamatory drugs, anticancer drugs,

5. Improved topical application: due to high lipid content when the drug is applied on the skin it will easily pass into the skin.ex: anesthetics, corticosteroids, insulin.

6. Treatment of infections(3): moat focused infections that are in focus are that caused by the fungus and leishmaniasis. Which mostly reside with in the macropahages as the drug is encapsulated with in liposome thus the passive targeting becomes easy. Further research on encapsulation of drugs for other chemotherapeutic effects is on role.

7. Vaccination: vaccines for the malarial are under the clinical trails.

8. Reduced toxicity(4): it was found that the anticancer drugs like doxorubicin and anthracyclins shows less toxicity when compared to free drug molecules. Other drugs are still in the clinical trails.

9. Diagnosis: cholesterol when combined with long and saturated hydro carbon chain form small liposomes which gets accumulated in the sites of the inflammation thus it can be used for the diagnosis.

10.Aerosols(5): liposomal aerosols prove to have longer duration of action when in treatment of asthma

11.Stealth liposomes(3): to mask the liposomes from the effect of the RES system they are coated with PEG, which enables its improved circulation. It was found that doxorubicin when encapsulated as stealth liposome it showed prolong duration of action due to increased time of circulation.

In this blog I have tried to provide an outline of different applications in the field of pharmacy. Research is going on in the industry for developing new formulations. Many drugs are still in clinical trails.

This blog is free from any plagiarized material.

Reference:

1. www.dr-baumann-international.co.uk/.../Applications%20of%20Liposomes (accessed on 22/04/2011)

2. www.unav.es/noticias/cruz.pdf (accessed on 22/04/2011)

3. en.wikipedia.org/wiki/Liposome (accessed on 24/04/2011)

4. www.hindawi.com/journals/jdd/2011/863734/ (accessed on 22/04/2011)

5. www.pharmasm.com/pdf_files/Umalkar.pdf (accessed on 22/04/2011)