Presented by

Ritu rawal

M pharmacy (pharmaceutics)

1

NIOSOMES

content

2

Introduction

Types of niosomes

Advantages and disadvantages of niosomes

Formulations of niosomes

Structural components of niosomes

Method of preparation

Characterization of niosomes

Applications of niosomes

INTRODUCTION

3

Niosomes are novel drug delivery system in which both

hydrophilic and hydrophobic drug is encapsulated in a

vesicle. This are non-ionic surfactant vesicles, which are

biodegradable , relatively non-toxic , more stable,

inexpensive and alternative to liposome.

They present a structure similar to liposomes they can

represent alternative to vesicular system with respect to

liposomes.

Niosomes basically made of non – ionic surfactant which

provide advantages over the phospholipids because they

are more economical and are chemically more stable as

they are not easily hydrolysed or oxidized during storage.

Types of noisome

4

Multi lamellar vesicles (MLV).

Large unilamellar vesicles(LUV)

Small unilamellar vesicles(SUV)

Multilamellar vesicles(MLV)

5

It consists of number of bilayer surrounding the

aqueous lipid compatment seperately. The

approximate size of this vesicles is 0.5 to 10 micro

meter diameter. This vesicles are most widely used

niosomes. It is simple to make and are mechanically

stable upon storage for long periods. These vesicles

are highly suited as drug carrier for lipophilic

compounds.

Large unilamellar

vesicles(LUV)

6

Niosomes of this type have high aqueous/lipid

compartment ratio , so that larger volume of bio-

active materials can be entrapped with a very

economical use of membrane lipid.

Small unilamellar

vesicles(SUV)

7

These small unilamellar vesicles are mostly prepared

from multilamellar vesicles by sonication method ,

french press extrusion electronic stabilization is the

inclusion of dicetyl phosphate in 5(6)–carboxy

fluorescein(CF) loaded span 60 based niosomes.

Advantages of niosomes

8

High patient compliance in comparision with oily

dosage forms as the vesicle suspension is a water –

based vehicle.

Accomodate drug molecules with wide range of

solubilities.

The characteristics of the vesicle formulation are

variable and controllable. Altering vesicle

composition , size, lamellarity , surface charge and

concentration can control the vesicle

characteristics.

The vesicles may act as a depot, releasing the

drug in a controlled manner.

cont...

9

They are osmoticallly active and stable , as well

as they increase the stability of entrappped drug.

Handling and storage of surfactants requires no

special conditions.

They improve oral bioavaibility of poorly absorbed

drugs and enhance skin penetration of drugs.

They can be made to reach the site of action by oral

penetration as well as topical route.

The surfactants are biodegradable , biocompatible

and non- immunogenic.

Disadvantage of niosomes

10

The aqueous suspension , of niosomes may have

limited shelf life due to fusion , aggregation ,

leaking of entrapped drugs , and hydrolysis of

encapsulated drugs.

The methods of preparation of multilamellar vesicles

such as extrusion , sonication, are time consuming

and may require specliazed equipment for

processing .

Formulation of niosomes

11

Surfactant; span 60

Cholesterol

Chloroform or methanol

Phosphate buffer

• Drug

Structure component of

niosomes

12

1. Surfactant

2. Ether linked surfactants

3. Ester linked surfactants

4. Cholesterol

5. Charge inducers.

Structure of vesicle

13

Non-ionic surfactants

14

Non –ionic surfactants posses hydrophilic head group and

hydrophobic tail .

The hydrophobic moiety may consists of 1/2/3 alkyl chains

or per fluro groups or in some cases a single stearyl groups .

Hydrophilic head groups affect on entrapment efficiency of

drug.

As HLB value increases alkyl chain increases , the size of

niosomes increases . Hence HLB value 14 -17 is not sutaible

for niosomes formulation, HLB value 8.6 have highest

entrapment efficiency , number between 4 and 8 was found to

be compatible with vesicle formation.

cholesterol

15

• The incorporation of cholesterol into bilayer composition

of niosomes gives membrane stabilizing activity and

decreases the leakiness of membrane.

• Hence incorporation of cholesterol into bilayer increases

the entrapment efficiency .

• Cholesterol is added usually to non-ionic surfactant to

give rigidity and orientation order to the niosomes bilayer

.

• Cholesterol is also known as abolish gel to liquid phase

transition of niosomes system resulting in niosomes that

are less leaky.

Other additives

16

Other additives include charge inducers which increase

surface charge density and prevent vesicles flocculation

, aggregation and fusion .

Both negatively and positively charged molecules are

used for induction of charge in niosomes.

Dicetyl phosphate and stearyl amine induces negative or

positive charge on membrane and thereby help to

stabilize the form

Method of preparation

17

1. Ether injection method

2. Thin film hydration technique.

3. Sonication method.

4. Reverse phase evaporation technique (REV)

5. Microfluidization

6. Multiple membrane extrusion method

7. Trans – membrane pH gradient (inside acidic) drug

process (remote loading)

8. Bubble method

9. Formation of niosomes from proniosomes.

Ether injection method

18

This method provides the means of making

niosomes by slowly introducing a solution of

surfactant dissolved in diethyl ether (volatile

organic solvent) into warm water maintained at

60⁰c .

The surfactant mixture in ether injection through

14 – gauze needle into an aqueous solution of

material .

Vaporization of ether leads to formation of

single layered vesicles.

Depending upon the condition used the

diameter of vesicle range from 50 to 1000 m.

Thin film hydration

19

All vesicles components i. e surfactant,cholesterol and charge inducers are disssolvedin volatile organic solvent in a round bottom flask.

Using rotary evaporator the organic solvent isevaporated at room temperature forming a thindry film of dissolved components.

The dried thin film is hydrated with aqueousphase with gentle agitation which leads toformation of niosomes.

The drug can be added to aqueous phase ifhydrophilic and can be dissolved in organicsolvent with other component if hydrophobic.

Characterization of niosomes

20

Size

Entrapment efficiency

Bilayer formation , membrane rigidity and

number of lamella

Factor affecting the physicochemical

properties niosomes:

21

Nature of surfactants: The surfactants with alkyl chainlength from C12-C18 are suitable for preparation ofnoisome.

Membrane additives: Stability of niosomes can beincreased by the number of additives into niosomalformulation along with surfactant and drugs. Themembrane stability, morphology and permeability ofvesicles are affected by numbers of additive e.g. additionof cholesterol in niosomal system increases the rigidityand decreases the drugs permeability through themembrane. Niosomes prepared by C16G2/cholesterol/MPEG- Chol show spherical vesicles withdiameters ranging from 20 nm to 200 nms

Cont...

22

Resistance to osmotic stress: Addition of a

hypertonic salt solution to a suspension of

niosomes brings about reduction in diameter. In

hypotonic salt solution, there is initial slow

release with slight swelling of vesicles probably

due to inhibition of eluting fluid from vesicles,

followed by faster release, which may be due to

mechanical loosening of vesicles .Drug: Entrapment of drug in niosomes

increases vesicle size, probably by interaction of

solute with surfactant head groups, increasing

the charge and mutual repulsion of the

surfactant bilayers, thereby increasing vesicle

size. The hydrophilic lipophilic balance of the

drug affects degree of entrapment

Cont...

23

• .

Cholesterol contents: The incorporation of

cholesterol into bilayer composition of niosome

induces membrane stabilizing activity and decreases

the leakiness of membrane. Hence, incorporation of

cholesterol into bilayer increases entrapment

efficiency. The permeability of vesicle bilayer to 5, 6-

carboxy flourescein (CF) is reduced by 10 times due

to incorporation of cholesterol

Applications of niosomes

24

Niosomes as drug carrrier: Niosomes have also

been used as carrier for iobitridal a diagnostic

agent used for x –ray imagining .

Targeting of bioactive agent : to reticulo –

endothelial system . The cells of RES

preferentially take up the vesicles .

Anti- neoplatic treatment : most–anti neoplastic

drug cause severe side effects. Niosomes can

alter the metabolism , prolong circulation and half

life of drug , thus decreasing the side effects of

drug.

Cont...

25

Localized drug action: drug delivery through

niosomes is one of the approaches to achieve

localized drug action. since their size and low

permeability through epithelium and connective

tissue keeps the drug localized at the site of

administration.

Niosomes formulation as a brain targeted delivery

system for the vasoactive intestinal peptide (VIP):

encapsulated VIP within glucosebearing niosomes

exibitis higher VIP brain uptake as compared to

control .

Niosomes as pulmonary drug delivery system.

Cont...

26

The vesicle suspension was water–based vehicle.

This will offers high patient compliance in

comparison with oily dosage forms.

They possess an infrastructure consisting of

hydrophilic, amphiphilic and lipophilic moieties

together and as a result could accommodate drug

molecules with a wide range of solubilities.

They improved oral bioavailability of poorly

absorbed drugs and enhanced skin penetration o f

drugs.

They could be made to reach the site of action by

oral, parenteral as well as topical routes.

Refrences

27

P Gadhiya, S shukla ,Niosomes in targeted drug

delivery A review, International Journal for

pharmaceutical Research scholars, 2012(1);61-

62.

Gurjar pravina , Naik Nivedita, Niosome: a

promising pharmaceutical drug delivery ,

International journal of pharmaceutics and

analysis ; 2014(2), 425-427.

Gandhi Arijit , suma Oomen sen, Current trend in

niosomes as vesicular drug system , Asian journal

of pharmacy and life sciences ; 2012 2(2), 340-

342

28