This document discusses nanoemulsions as a novel drug delivery system. It defines nanoemulsions as thermodynamically stable isotropic mixtures of immiscible liquids stabilized by surfactants, with droplet sizes ranging from 50-500nm. Advantages include increased drug absorption and bioavailability, stability without sedimentation, and various routes of administration. Limitations are the expensive production processes and potential stability issues from changes in pH or osmotic pressure. Characterization methods described include measuring droplet size, surface charge, viscosity, and refractive index. Applications discussed are parenteral, ocular, pulmonary, transdermal, intranasal, and oral drug delivery as well as tumor targeting.

1. Presented by-
Anup Kumar
Dept. of Medical devices
(NIPERA1618MD01)

2. INTRODUCTION
Nanoemulsions may be defined as the novel drug
delivery system which is thermodynamically stable,
isotropic in nature where two immiscible liquid i.e a
water system & a oil system are mixed together to form
a single phase by means of an apporopriate
surfactant.In nanoemulsion the oil droplets
containing the hydrophobic drug that has to be
delivered to a targeted organ and the mean droplet
diameter ranging 50-500 nm.

3. Basic structural view of
Nanoemulsion system

4. Advantages of Nanoemulsions
 Nanoemulsions increase the rate of drug absorption.
 The very small droplet size causes a large reduction in the gravity
force and the brownian motion is sufficient for overcoming gravity
.This mean that no creaming or sedimentation occurs on storage.
 It helps to solubilize lipophilic drugs.
 Various routes like topical,oral,I.V. etc. can be used to deliver the
product.
 It improves the bioavailability of drugs.
 It can be formulated in varity of formulation such as foams,
liquids,sprays &creams.
 It may be used as a substitute for liposomes.
 It is thermodynamically stable.
 Possibilities of controlled drug release & drug targeting.

5. Limitations of Nanoemulsions
The formulation of nanoemulsions is an expensive
process due to size reduction of droplets is very
difficult as it required special kind of instruments &
prrocess methods.For example homogenizer
arrengement is an expensive process.
Oswald ripening could damage the nanoemulsions.
Changing of pH may cause stability problems.

6. Difference between Emulsions
&Nanoemulsions
EMULSIONS NANOEMULSIONS
1. Anisotropic
2. Appearance is cloudy
3. Thermodynamically
unstable.
4. Wet gum method,Dry
gum method are used for
preparation.
5. Higher surfactant
concentration(20-25%)
6. Creaming ,sedimentation
&phase inversion etc
stability problem may occur.
1. Isotropic
2. Appearance is transparent.
3. Thermodynamically stable
4. Microfludization,ultraso
und generators etc.
technique are used for
preparation.
5. Lower surfactant
concentration(5-10%)
6. These type of problems not
occur.

7. Formulation of Nanoemulsions
 Oil phase- Captex,isopropyl myristate,castor oil etc.
 Surfactants-potassium & sodium stearate,isopropanol
amine,N-dodecyl alanine,cetrimide,benzalkonium
chloride,tween 20,macrogol esters etc.
 Co-surfactants-Ethanol,propanol,propylene glycol
etc.
 Antioxidants
 Tonicity modifiers
 pH adjusting agents
 Preservatives

8. Preparation of Nanoemulsions
 High-energy emulsification method- This
emulsification method involve high mechanical energy.
 There are several devices like the rotor/stator,sonifiers
or ultrasound generator ,high pressure homogenizers
etc.used to force the creation of huge interfacial areas.
 Low-energy emulsification method-Require low
mechanical energy for fabrication of emulsions.Subsequent
emulsification & phase inversion technique are used.
 Preparation of homogeneous organic solution>organic
phase added in the aqueous phase >removal of water
miscible solvent by evaporator.

9.  Micro fluidization
This device uses a high
pressure positive displacement
pump(500-20000psi),which
forces the coarse emulsion
through the interaction
chamber which consist of a
small channels called Micro-
channels.
The product flows through
the Micro-channels which
resulting in very fine particles of
nano range.

10. Preparation of Nanoemulsion

11. Characterization of Nanoemulsion
 Preliminary characterization
 Morphology and structure
 Invitro skin permeation study
 Droplet size analysis
 Refractive index
 Surface charge(zeta potential)
 Viscosity

12. Viscosity
Increasing the water content
lowers the viscosity of
nanoemulsion while decrease
the amount of surfactant or
co-surfactant increase the
interfacial tension between
water and oil resulting in
increase viscosity.

13. Droplet size Analysis
It is done by using helium-
neon laser having a
particular wavelength of
632.8 nm.

14. Surface charge
It is determined by the using of
Zetasizer Nano Z . Zeta potential
characterizes the surface charge of
particles. Thus it gives
information about repulsive
forces between particles and
droplets.
To obtain stable nanoemulsion
zeta potential should have a value
about 30mV.

15. Refractive index
The refractive index of
nanoemulsion formulation is
determined by using abbe
type refractometer. It gives
the information about
isotropic nature of
nanoemulsion system.

16. Applications of Nanoemulsion in
drug delivery system
Parenteral drug delivery
Ocular drug delivery
Pulmonary drug delivery
Transdermal or Topical drug delivery
Intranasal drug delivery
Tumor targeted drug delivery for cancer therapy
Oral drug delivery

17. Parenteral drug delivery
Both o/w & w/o nanoemulsions system can be used.
Generally I.V route is preferred.
Nanoemulsion is cleared more slowly than the coarse
particle emulsion and therefore have a longer
residense time in body.
Frequency of dosage of injection can be reduced
throughout the drug therapy.
Parenteral nanoemulsion formulation of the following
drugs have been documented-
carbamazepine,diazepam,dexamethasone etc.

18. Intranasal Drug delivery
Used as a vehicle system for brain targeted drug
delivery.
Nanoemulsions loaded with drugs like risperidone
,rizatriptan etc. are very useful in the treatment of
CNS disorders like parkinson’s,migraine,meningitis
etc.

19. Ocular drug delivery
Nanoemulsions increase the contact time of the
drug in the eye.
High ability of drug penetration into the deeper
layers of the ocular structure & aqueous humor.
Reduce the need for frequent administration.
Nanoemulsions of dorzolamide.Hcl shows high
therapeutic efficacy & prolonged effect.

20. Tumor targeted drug delivery
 Act as a vehicles for targeted drug delivery of various
aqueous insoluble anti cancer
drugs,photosensitizers,diagnostic agents for cancer
therapy.
 Devolpement of magnetic nanoemulsion is an
innovative approach for cancer therapy.These can be
deliver photosensitizers like Foscan to deep tissue
layers across the skin thereby inducing
hyperthermia.

21. Pulmonary drug delivery
To achieve relatively uniform distribution of drug
dose among the alveoli.
Able to transfect pulmonary epithelial cells.
A novel pressurized aerosol system for the pulmonary
delivery of sulbutamol.

22. Oral drug delivery
 Nanoemulsions was devoloped to increase oral
bioavailability of hydrophobic drugs.
 GIT distrubances can be avoided.
 High concentration of paclitaxal was observed in the
systemic circulation when it is formulated in
nanoemulsion form.

23. Transdermal drug delivery
Nano sized emulsions are able to easily penetrate the
pores of the skin and reach the systemic
circulation.Thus getting channelized for effective
drug delivery.
Able to controlled the locally applied drug
redistribution through cuteneousblood&lymphvessle
system.
w/onanoemulsionsof caffeine,indomethacin
,aceclofenacetc.havebeendevelopedfortransdermaldrug
delivery.

24. Others Applications…
 Antimicrobial Nanoemulsions
 Cell culture Technology
 Vaccines delivery

25. Future Perspective…
 Future perspectives of nanoemulsions are very
promising in different fields of drug delivery for more
efficacy , applications in development of cosmetics for
skin.
 May be become ideal drug delivery platform for the
phyto pharmaceuticals.

26. Conclusion…
 Nanoemulsions offers several advantages as well as
applications for novel drug delivery and thus receiving
increasing attention as drug carriers for improving the
delivery of active pharmaceutical ingredients.
 They can applicable for almost all routes of drug
delivery and therefore hold the promises for different
pharmaceutical field.This new approach could be
devoloped to overcome the problem associated with
the treatment of AIDS, genetical disorders and its own
stability problems etc.