Liposomal Drug Delivery in pharmaceuticals

Liposomal Drug Delivery in pharmaceuticals

1. Dr. B. Sree Giri Prasad Associate Professor Nalla Narasimha Reddy Education Society’s Group of Institutions

2. Classification of Liposomes Materials used in Preparation of Liposomes Methods of Liposome Preparation Characterization of Liposomes CONTENTS Stability Therapeutics Application Introduction Structure Unique Properties of Liposomes Advantages Disadvantages Liposomes Evolution Components of Liposomes

3. The word “ Liposomes” word is derived from Greek Word, Where “ Lipo ” means “Fat” & “Some” means “Body”

4. Liposomes are : Self closed Structures Composed of curved lipid bilayers Spherical in which an aqueous volume is entirely enclosed by a membrane composed of lipid molecule Structurally liposomes are concentric bilayered vesicles in which an aqueous volume is entirely enclosed by a membranous lipid bilayer mainly composed of natural or synthetic phospholipids Their size ranges from 20 nm to several dozens µm . While thickness of the membrane is around 4 nm .

5. . Structure: Phospholipids are the building blocks of liposomes & Cell Membranes . Phospholipids are a special group of lipids containing Phosphate . Lipids in general are hydrophobic, also called non-polar. However, the phosphate group in phospholipids is hydrophilic , also called polar.

6. Phospholipids are : Phospholipids are Amphiphilic moieties with a Hydrophilic Head Group & Two Hydrophobic Tails . Two types of Phospholipids exists- Phosphodiglycerides & Sphingolipids , together with their corresponding Hydrolysis products Fatty substances which acts major structural component of Cell wall & Biological Membranes There are various components contained in liposome , however Lecithin ( Mixture of Phospholipids & Cholesterols) being main components. Composition of Liposome :

7. Phospholipids have Phosphatidyl moiety (Tail) with different Head Groups ( Choline , Ethanolamine , Serine ) The most common phospholipid is Phosphatidylcholine ( PC ) molecule.

8. The interaction between phospholipids and water takes place at a temperature above the gel to liquid-crystalline phase transition temperature (TC) Which represents the melting point of the acyl chains. When phospholipids are immersed in water they arrange themselves so that their hydrophilic regions point toward the water and their hydrophobic regions point away from the water and stick together in bilayer form.

9. These Vesicles can encapsulate Water-Soluble Drugs in their aqueous spaces and Lipid Soluble Drugs within the membrane itself . Unique Properties of Liposomes: Biodegradable Hypoallergenic Nature Versatile Because of Similarity to biological membranes, results to develop Liposomal Drug Delivery Systems.

10. Biodegradable Non Immunogenic Non Toxic Lowers Systemic Toxicity Provides Selective Passive Targeting to Tumor Tissues – Targeted Drug Delivery Protection of Sensitive Drug Molecules Increased Efficacy & Therapeutic Index Advantages: Protection of Sensitive Drug Molecules Enhanced Drug Solubilization (Amphoterecin)

11. Increased Stability via Encapsulation Reduction in Toxicity of the encapsulated agent Improved Pharmacokinetic Effects Used as Carriers for Controlled & Sustained Drug Delivery Can be made into variety of Sizes

12. Uptake of Liposomes by Reticuloendothelial System Short Half-life Leakage of Encapsulated Drug During Storage Batch to Batch Variation Difficult in Large Scale Manufacturing & Sterilization Production Cost is High. Once Administered, Liposomes can not be removed Disadvantages: Possibility of Dumping, due to faulty administration Some times Phospholipids undergoes Hydrolysis & Oxidation Reactions.

13. https://www.slideshare.net/DanishKurien/liposomes-9644602 https://www.slideshare.net/anirbansaha9809/liposomes-44696108 https://slideplayer.com/slide/8303005/ https://slideplayer.com/slide/8015293/ https://slideplayer.com/slide/13062883/