Novel Drug Delivery System Niosomes Topic.

1. Niosomes as
Drug Carriers:

2. Introduction:
Target drug delivery system is a special form of drug delivery system where the
pharmacologically active agent or medicament is selectively targeted or delivered only to
its site of action or absorption and not to the non-target organs or tissues or cells.
So basically Neosomes comes under
Drug- Carrier Systems of Target Drug
dilivery System and act as Drug
Carriers.

3. What are Niosomes ?
Niosomes are a novel drug delivery system, in which the medication is
encapsulated in a vesicle of a bilayer of non-ionic surfactants.
They are structurally similar to Liposomes and having alternative
Vesicular Systems with respect to Liposomes.
Types Of Niosomes:
1. Small Unilamellar Vesicles (SUVs)
2. Multi-Lamellar Vesicles (MLVs)
3. Large-Unilamellar Vesicles (LUVs)

4. Structure:
Microscopic Lamellar Structures formed by
1. Non-Ionic Surfactant
(polyglycerol alkylethers, glucosyl dialkylethers and polyoxyethylene
alkylethers.)
2. Cholesterol
(membrane permeability, rigidity, encapsulation efficiency, ease of
rehydration of freeze dried niosomes and their toxicity.)
3. Charge Molecules
(to increase stability by electrostatic repulsion which prevents aggregation
and coalescence
The negatively charged molecules used are diacetyl phosphate (DCP) and
phosphotidic acid. Similarly, stearylamine (STR) and stearyl pyridinium
chloride are the well. Known positively charged molecules )

5. Method of Preparation:
1. Ether Injection (LUV)
2. Hand Shaking Method (MLV)
3. The “Bubble” Method
4. Reverse Phase Evaporation (LUV)
5. Sonication (SUV)
6. Multiple membrane extrusion method
7. Trans Membrane pH Gradient Drug Uptake
Process (remote Loading) (MLV)
8. Microfluidization method (SUV)
9. Formation of Niosomes From Proniosomes

6. Evaluation:
1. Size , Shape and Morphology
2. Entrapment Efficiency
3. Osmotic Activity
4. Vesicle Surface Charge
The applications of niosomes can be mainly classified into three
categories
1) For Controlled Release of Drugs
2) To Improve the Stability and Physical
Properties of the Drugs
3) For Targeting and Retention of Drug in Blood Circulation.

7. Advantages of Niosomes:
1.Targeted drug delivery can be achieved the drug is delivered directly to
the body part where the therapeutic effect is required.
2. Reduced dose is required to achieve the desired effect
And Subsequent decrease in the side effects
3. The therapeutic efficacy of the drugs is improved by reducing the
clearance rate, targeting to the specific site and by protecting the
encapsulated drug.
4.The surfactants used and also the prepared niosomes are biodegradable,
biocompatible and non-immunogenic.
Dis-Advantages :
Aqueous suspension of niosome may exhibit fusion, aggregation leaching or
hydrolysis of entrapped drug, thus limiting the shelf life of niosome dispersion.
• Time consuming
Requires specialized equipment
• Inefficient drug loading