Liposomes are vesicular structures composed of lipid bilayers that encapsulate an aqueous core. They can be used to improve drug delivery by modifying drug absorption, prolonging drug effects, and reducing toxicity. Liposomes are classified based on their composition and applications, such as conventional, long-circulating, and polymeric liposomes. They have various applications in drug delivery, including cancer chemotherapy and topical administrations, by facilitating targeted and controlled release of drugs. Future liposome technologies may include niosomes, ethosomes, and vesicles for multi-drug formulations and gene delivery.

1. LIPOSOMES:
On The
Drug Delivery Highway
Presenter
Rasheed Perry
MPhil Student
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2. Definition of Terms
 Drug Delivery: Formulation or device
that delivers drug to a to a specific site
in the body at a certain rate
 Targeted drug delivery: Drug is
delivered to specific sites in the body
 Bioresponsive release: Drug delivery
is controlled by a biological stimulus
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3. Definition of Terms
 Amphipathic: possessing both a
Hydrophilic (water loving) and
hydrophobic (water hating) regions
 Lipid bilayer: Composed of a phosphate
region (hydrophilic) and lipid group
(hydrophobic)
 Maximum Therapeutic Effect: A medical
treatment of any kind, the results of
which are judged to be desirable and 3

4. Outline
 The Advent of Liposomes
 Advantages & Disadvantages
 Classification
 Preparation
 Applications
 Future Technology
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5. The Advent of Liposomes
 What are these chemical
compounds’?
 Vesicular structures based on one or
more lipid bilayers encapsulating an
aqueous core.
 The lipid molecules are usually
naturally occurring or synthetic
phospholipids, amphipathic
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6. The Advent of Liposomes
 First Discovered by in 1961
 Were initially Called bangosomes
 Then Liposomes were derived by the
combination of the Greek words
 “Lipos” – meaning Fat
 “soma” – meaning Body
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7. Liposomes
 Lipid Bilayer
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8. Liposomes
 Vesicle
Phosphate
Group
Hydrophilic
Lipid Tale
Hydrophobic
A
B
C
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9. ADVANTAGES
Used to Improve the Therapeutic Index of new and
established Drugs:
 Modifying Drug Absorption
 Reducing Drug Metabolism by the body
 Prolonging Biological Half life
 Reducing Toxicity
 Allows for Controlled/Directed action
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10. Classification of Liposomes
 Based on Application &
Composition:
 Conventional Liposomes
 Long circulating Liposomes
 Polymeric Liposomes (pH sensitive,
cationic and thermo-sensitive)
 Decorated Liposomes
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11. Conventional Lipososmes
 Made exclusively of lipids
 Was the first form of liposomal drug
delivery explored
 Impacted by the Mononuclear
Phagocyte System
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12. Conventional Lipososmes
B C
A
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13. Long circulating Liposomes
 Long-circulating liposomes present a
chemical substance called a polymer
on its surface
 Conventional and long-circulating
liposomes may present a slow release
of the active substance into the cell
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14. Long circulating Liposomes
A
B C
Sahsi et al, 2013
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15. Polymeric Liposomes (pH
sensitive, cationic and thermo-
sensitive)
 Polymorphic liposomes have been
developed to address many issues,
 Mainly due to the fact that these
liposomes become reactive when
submitted to membrane changes
 Triggered by pH, variations in
temperature, or surface charge
alterations.
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16. Decorated Liposomes
 Improved specificity of liposomes for
injured organs or tissues and to
prevent their uptake by the healthy
tissues
 Developed by binding specific ligands
 Capable of directing the liposomes to
the region of interest through active
targeting 16

17. Preparation of Liposomes
Traditional Preparation Method
 Lipids and hydrophobic drugs are
combined in a organic solvent
 Evaporation (Rotary)
 Dry lipid Film
 Dry film is hydrated with hydrophilic dug
in water solution
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18. Preparation of Liposomes
 Stiring (Multilamellar Vesicles)
 Size Reduction (sonification,
homogenization)
 Large Unilamellar Vesicles and Small
Unilamellar vesicles
 Purification
 Final Liposome
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19. Applications
of Liposomes
in
Drug Delivery
19

20. PRINCIPLE OF DRUG
TARGETING
Non-
Target
site
Target
Site
Free Drug Drug in Carrier
Affinity
Effect:
Toxicity
Little Affinity
Limited
Effect
Facilitated
Transport
Effect:
Targeting
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21. Applications of Liposomes in
Drug Delivery
 Because of their efficiency in drug
delivery, their use is vast and wide.
 Cancer chemotherapy
 Antimicrobial therapy
 Topical administration
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22. Applications of Liposomes in
Drug Delivery
 According to a review article published
by Drug delivery Today, a Phase 111
was conducted with women with
recurrent ovarian cancer
 Were not responsive to first line
platinum chemotherapy
 These women were then treated with
PEGylated Liposome doxorubicin
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23. Applications of Liposomes in
Drug Delivery
 Response Rates: 19.7% vs 17.0%, P
value 0.397
 Valuable treatment option in treatment
of ovarian carcinoma
 Has been shown significant also in
breast cancer management,
haematological malignancies
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24. Applications of Liposomes in
Drug Delivery
 Another article titled liposome:
classification, preparation and
application published in the
Springeropen Journal also highlights
the use of liposomes in cancer therapy
 Anthracyclines: (stop the growth of
dividing cells, by interfering with DNA)
◦ Affects hair, gastrointestinal tract and
blood cells
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25. Applications of Liposomes in
Drug Delivery
 Shows reduced toxicities when
administered and increased efficacy.
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26. Applications of Liposomes in
Drug Delivery
 A review article in International Journal
of Current Research pharmaceutical
research also highlighted the use of
lipososmes in Topical administrations
 Liposomes have a similar lipid make
up as the membrane covering of the
skin.
 This allows for the absorption of the
liposome into the skin and the
subsequent release of its contents.
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27. Applications of Liposomes in
Drug Delivery
 Incorporation of rifabutin in liposomes
resulted in a significant enhancement
of
activity against Mycobacterium avium
infection compared to free rifabutin.
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28. Applications of Liposomes in
Drug Delivery
Product
name
Route of
administrat
ion
Drug Approved indication
Ambisome Intravenous Amphotericin
B
Sever fungal infections
Visudyne Intravenous Verteporfin
Age-related molecular
degeneration, ocular
histoplasmosis
T4N5
liposome
lotion
Topical
Bacteriophage
T4
endonuclease 5
xeroderma
pigmentosum.
Arikace
portable
aerosol
delivery
Amikacin Lung infection
International Journal of Nanomedicine,
2011
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29. Future Technology
Type Application
Niosomes Less prone to action of bile salts
Ethosomes Better absorbed for transdermal
delivery
Cryptosomes Increased Stability
Vesosomes Sustained release of drug/
Multidrug formulation possible
Genosomes Suitable for Gene Delivery
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30. Summary
 The advent of liposomes has led to a
more precise and controlled delivery
of many drugs, through the properties
of stability, protection and targeted
release. On this our Drug Deliver
Highway, Liposomes have proven to
be the license our Drugs need to
execute their effect
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31. 31

32. References
 Akbarzadeh et al(2013).Liposome:
Classification, preparation and
application. Retrieved on 6th of March
2015 from website:
http://www.ncbi.nlm.nih.gov/pmc/articl
es/PMC3599573/
 Caldeira et al(2013). Liposomes as
Carriers of Anticancer Drugs.
Retrieved on 4th of March 2015 from
website:
http://www.ncbi.nlm.nih.gov/p
mc/articles/PMC3599573/
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33. References
 Drug Delivery Today(2012). Liposomal
formulations in cancer therapy: 15 years long
the road. Retrieved on 4th of March, 2015
from website:
http://csmres.co.uk/cs.public.upd/articl e-
downloads/slingerland_2012_drug-
discovery- today.pdf
 International Journal of Current Pharmaceutical
Research (2011).
LIPOSOMES: A NOVEL DRUG DELIVERY
SYSTEM. Retrieved on the 6th of March from
website:
http://www.ijcpr.org/Issues/Vol3Issue2/2
92.pdf
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34. References
 International Journal of Nanomedicine
(2011). Liposome-based drugs on market.
Retrieved on April 13, 2015 from
website:
http://www.ncbi.nlm.nih.gov/pmc/articles/
PMC 3260950/table/t1-ijn-7-049/
 Sahsi et al(2013). A Complete Review On:
Liposomes. Retrieved on 4th of March
2015 from website:
http://www.intechopen.com/books/can
cer- treatment-conventional-and-
innovative- approaches/liposomes-as-
carriers-of- anticancer-drugs
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35. References
 Singh et al (2014). PHARMACOSOMES: A
NOVEL CARRIER FOR TARGETED
ANDCONTROLLED VESICULAR DRUG
DELIVERY SYSTEM. Retrieved on 7th of
March 2015 from website:
file:///C:/Users/rasheed.perry/Downloads/ar
ticle_wjpr_1406265912.pdf
 Sinko et al.(2011). Martin’s Physical
Pharmacy and Pharmaceutical
Sciences. 6th edition. Lippincott
Williams and Wilkins, China
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