“LIPOSOMES- A NOVEL VESSICULAR CARRIER” Presented By Mr. Bhosale Pramod Motiram M. Pharm (SEM- I) Pharmaceutics Roll No-02 Guided By- Prof. A. W. Ambekar M. Pharm. Pharmaceutics . A Seminar on DR.VITHALRAO VIKHE PATIL FOUNDATION’S COLLEGE OF PHARMACY, AHMEDNAGAR. 1
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“LIPOSOMES- A NOVEL VESSICULAR CARRIER”
Presented ByMr. Bhosale Pramod
Motiram
M. Pharm (SEM- I)Pharmaceutics
Roll No-02
Guided By-Prof. A. W. Ambekar
M. Pharm. Pharmaceutics
.
A Seminar on
DR.VITHALRAO VIKHE PATIL FOUNDATION’S COLLEGE OF PHARMACY, AHMEDNAGAR.
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Introduction Advantages & Disadvantages Mechanism of liposomes action Classification Types Of Liposomes Method of Liposome Preparation Evalution of Liposomes Applications Recent Advances Some marketed Preparation
CONTENTS
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Liposomes are simple microscopic , concentric bi-layered vesicles in which an aqueous
volume is entirely enclosed by a membranous lipid bi-layer mainly composed of
phospholipids and cholesterol.
Liposomes were discovered by Bhangam and co-workers in 1960’s in England.
The size of a liposome is upto 20 nm
Liposomes are the drug carrier loaded with great variety of molecules such as small drug
molecules, proteins, nucleotides & even plasmids.
Liposomes can be produced from cholesterols, non toxic
surfactants,sphingolipids,glycolipids,long chain fatty acids & even membrane proteins.
INTRODUCTION
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General structure of liposome
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ADVANTAGES: Biocompatibility and Biodegradability. Easy to manufacture. Targeted drug delivery Prolonged circulation in stealth mode Able to protect encapsulated drug from degradation.
Phospholipids of liposome are incorporated into cell membrane
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Classification BASED ON STRUCTURE : Multi-lamellar large vesicles (>0.5 µm) MLV Oligo-lamellar vesicles (0.1 – 1µm) OLV Uni-lamellar vesicles ( All size ranges) UV Small uni-lamellar vesicles (20 – 100 nm) SUV Medium size uni-lamellar vesicles (>100 nm) MUV Large uni-lamellar vesicles (>100 nm) LUV Giant uni-lamellar vesicles (>1 µm) GUV Multi-vesicular vesicles (>1 µm) MV
BAESD ON LIPOSOMAL FORMATION: Reverse phase evaporation REV Multi-lamellar vesicle by REV MLV-REV Stable plurilamellar vesicle SPLV Frozen and thawed MLV FATLV Vesicles prepared by extrusion techniques VET Dried reconstituted vesicles DRV
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There are two type of liposomes based on their structure.
a) Unilamellar liposomes: Unilamellar vesicles has a single phospho-lipid bilayer
sphere enclosing aqueous solution.
b) Multilamellar Liposomes: Multilamellar vesicles have onion structure. Typically,
several Unilamellar vesicles will form one inside the other in diminishing size,
creating a multilamellar structure of concentric phospholipid spheres separated by
layers of water.
Types of Liposomes
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a) Handshaking Method-
b) Sonication Method-
Methods of Liposomes Preparation
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There are two sonication techniques:
i) Probe Sonication
ii) Bath Sonicator
c) Reverse Phase Evaporation Method:-Lipid organic solvent aqueous solution
mix
sonicate
formation of w/o emulsion
evaporate to remove the organic solvent
Lipids form a phospholipid bilayer
vigorous shaking
water droplets collapse
formation of LUV’s.
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d) Freeze Dried Rehydration Method:- It is obtained from Pre-formed liposomes. Small macromolecule can be achieved in this. During dehydration, lipid bilayer & material are
encapsulated in liposomes. They are braught in closed contact. Aqueous phase should be added in small portion to
get Rehydration Method.
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Evaluation could be classified into three broadCategories,
1. Physical2. Chemical3. Biological parameters.
Techniques:- Microscopic Techniques1. Optical Microscopy2. Cryo-Transmission Electron Microscopy Techniques (cryo-TEM) Diffraction and Scattering Techniques Hydrodynamic Techniques
EVALUTION OF LIPOSOMES
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Formulation of antineoplastic drugs into liposomes will significantly enhances systemic
circulation time.
Decreased toxicity by reducing free drug levels in plasma.