Liposomes : Modified Drug Delivery System

1. h
1
Presented by:
Aditya Singh
PhD (Pharmaceutics)
2001014
Applied Pharmaceutics

2.  Introduction
 Advantages
 Disadvantages
 Extraction Method
 Formulation of Liposome
 Liposomal examination
 In vitro drug release study
 Storage Stability study of liposomes
 Scanning Electron Microscopy (SEM)
 pH
2

3. 3
Fig 1. Liposome

4.  Liposomes were first described by British hematologist Alec
D Bangham in 1961 (published 1964).
 Liposomes are small artificial vesicles of spherical shape and
composed of one more phospholipids bilayer and an aqueous
core at the centre and have amphipathic in nature.
 Liposomes, were consists of Lipos (fat) + soma (body).
 Liposomes composed of lecithin which are used as
encapsulator antioxidant and cholesterol is an important
component of biological membrane.
4

5.  Liposomes increased efficacy and therapeutic index of
drug.
 Liposome increased stability via encapsulation.
 Liposomes are non-toxic, flexible, biocompatible,
completely biodegradable, and non-immunogenic for
systemic and non-systemic administrations.
 Liposomes reduce the toxicity of the encapsulated
agent.
 Liposomes help to reduce the exposure of sensitive
tissues to toxic drugs site avoidance effect.
 Flexibility to couple with site-specific to achieve active
targeting.
5

6.  Low solubility.
 Short half-life.
 Leakage and fusion of encapsulated.
drug/molecules.
 Production cost is high.
6

7. 7
Fig 2. Types of liposomes formation

8. 8
Fig 3. Liposome preparation

9. 9
Fig 4. Microscopic examine of liposomes formation

10.  pH
 Spreadability studies
 Viscosity
 Drug entrapment studies
 SEM
10

11. 11
Rheological analysis of the experimental liposome was performed by using
Rheometer.
Fig 5 . Types of liposomes formation

12. 12
The release studies were carried out in 250 ml beaker containing 100
ml of phosphate buffer pH 6.8. The beaker was assembled on a
magnetic stirrer and the medium was equilibrated at 37±50C. Dialysis
membrane was taken and one end of the membrane was sealed.
Fig 6 . In vitro release of liposomes

13.  Entrapment efficiency of liposomes was
determined by centrifugation method, the
liposomes were subjected to centrifugal on a
laboratory centrifuge (Remi R4C) at 3500 rpm
at 5ºC for a period of 45 min to separate the
free drug from solution.
13

14.  Emission Scanning Electron Microscope (SEM)
provides the surface morphology of the sample.
14

15.  The pH of liposomes formulations was determined by using
digital pH meter. About 1g of the liposomes was weighed and
dissolved in 100 ml of distilled water and stored for 1 hours.
15
Fig 7 . pH parameter for liposome testing

16.  Site specific targeting.
 Sustained / controlled release.
 Gene therapy.
 Herbal preparation.
 Anti-Aging.
 Ocular delivery of antibiotic.
16

17. 17

18.  Bangham A, Standish M.M, Watkins J, 1965, Diffusion of univalent ions across the
lamellae of swollen phospholipids, Journal of Molecular Biology, Vol. 13, pp. 238-
252.
 Torchilin, V, Weissig, V, 2003, Liposomes: A Practical Approach. Oxford
University Press: Kettering, UK, Vol.4, pp.77-101.
 Vemuri S, Rhodes CT, 1995, Preparation and characterization of liposomes a
therapeutic delivery system, a review, Pharmaceutica Acta Helvetiae, 70(2), 95-
111.
 Khan I, Elhissi A, Shah M, Alhnan MA, Waqar A, 2013, Liposome based carrier
systems and devices used for pulmonary drug delivery, In: DAVIM JP (ed.)
Biomaterial and medical tribology research and development, pp. 395-443.
 Khan I, Yousaf S, Subramanian S, Alhnan M A, Ahmed W, 2007, Proliposome
Powders for the Generation of Leptosomes, the Influence of Carbohydrate Carrier
and Separation Conditions on Crystallinity and Entrapment of a Model Antiasthma
Steroid, AAPS Pharm SciTech, pp.1-13.
18

19. 19