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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.
DISADVANTAGES: Poor stability High manufacturing cost Poor loading capacity Challenging sterilization Poor reproducibility
Advantages & Disadvantages
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Mechanisms by which liposomes act
Outside of the cell.
Liposome
Inside of cell.
Inside of cell.
Drug releasing into cell
Cell membraneCell
membrane
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.
Increased EPR (Enhanced permeability &retention effect).
Decreased cardio-toxicity of Doxorubicin by liposomal encapsulation.
Positively charged liposomes have enhanced immunogenic properties for vaccines and
hypersensitivity responses.
PEGylated liposomes are recent advancement in brain targeted drug delivery systems.
Liposomes used as drug carriers for efficient treatment of neuronal inflammation (Methyl
prednisolone) & others exhibited superior anti inflammatory activity than Other activity.
APPLICATIONS
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1) Liposomes in Cancer2) Sustain release Liposomes3) Liposomes in Gene Delivery4) Lipsomes for Protein & Peptide Delivery5) Liposome for Oral administration6) PH Sensitive Liposomes7) Antibody Mediated targeting liposomes
RECENT ADVANCES IN LIPOSOMES
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Brand Name Drug Category RouteDoxil Doxorubicin Anticancer Intravenous
Daunoxome Daunorubicin Anticancer Intravenous
Epaxel Hepatitis A vaccine
Protection against
Hepatitis
Subcutaneous
Elamax Lidocaine Local anesthetic Topical
Mikasome Amikacine Antibacterial Intravenous
SOME MARKETED PREPARATIONS
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Vyas S.P., Khar K.R. Trageted and Controlled drug delivery. CBS Publisher and distributors, New Delhi. 2002; 1;181,187.
Riaz.M. Liposomes preparation method pakisthan journal of pharmaceutical sciences. 1996; 19(1); 65-77.
Lipowsky R. Nature 1992; 349: 475–481. Lasic DD. Elsevier Amsterdam 1993;231.
Svetina S and B Zeks. Biophys Acta 1982; 44: 979–986.
Alving C. R. et al., Therapy of Leishmaniasis: Superior Efficacies of Liposome‐Encapsulated Drugs, Proc. Natl. Acad. Sci.
(USA),1978, 75, 2959–2963.
Lopez‐Berestein G. et al., Liposomal Amphotericin B for the treatment of Systemic Fungal Infections in Patients with
Cancer: A Preliminary Study, J. Infect. Dis., 1985, 151, 704–710.
Gregoriadis G. Genetic Vaccines: Strategies for Optimization, Pharm. Res., 1998, 15, 661–670.
Spanjer H. H., Scherphof G., Targetting of lactosylceramidecontaining liposomes to hepatocytes in vivo. Biochim
Biophys.Acta, 1983, 174, 40‐47.
Nicolau C., Legrand A., Grosse E., Liposomes as carriers for in vivo gene transfer and expression, Methods in
enzymology,1987, 149, 157‐176.
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REFERENCE
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THANK YOU…
SUCCESS IN LIFE MOSTLY DEPENDS ON THE POWER OF ‘CONCENTRATION’
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