Nanoemulsions

NanoemulsionsApplication of Nanotechnology in Drug Delivery

Antonio Di Martino

Nanoemulsions

• Dispersion of two immiscible liquids stabilized by a surfactant

• Thermodynamically and kinetically stable

• Droplets from 5 to 200 nm

Nanoemulsions Emulsion

Microemulsion

Nanoemulsion

Thermodynamically unstable Opaque High energy required to form

Thermodynamically stable Clear It forms spontaneously

Thermodynamically or kinetically stable Clear High shear application to form

Int. J. Nanomed. 2014,9,pp 1-8

Nanoemulsions - Classification Depending on the composition :

O/W : oil droplets dispersed in continuous aqueous phase

W/O : water droplets are dispersed in continuous oil phase

Bi-continuous : microdomains of oil and water are dispersed within the system

J. Mat. Chem. 2012, 22, pp 9767-9773

Nanoemulsions - Preparation

Materials

Methods

Low energy methods High energy methods

Phase Inversion Temperature Phase Inversion Composition Solvent Displacement

Use of devices with high mechanical energy to create nanoemulsions

Oils Surfactants Aqueous phase

Capryol90 Lauroglycol90 Labrafil CS Poloxamer124 PEG4000

Captex 355 Captex 8000 Witepsol Myritol 318

Nanoemulsions - Characterization

Morphology

Size, PDI

Viscosity

Skin permeation

Surface characterization

Refractive Index

Nanoemulsions - Applications

Agriculture

Cleaning products

Cosmetic

Pharmaceutic

Biomedical

Nanoemulsions - Drug DeliveryAdvantages Increase drug loading Enhance drug solubility Bioavailability Controlled drug delivery Protection of drug

Disadvantages Expensive process Stability Solubility Lack of understanding of interfacial chemistry More proofs about more benefits compared to classical macroemulsions

J. Phys. Chem. C 2008, 112 (33), 12669-12676.

Commercially Available Nanoemulsions

Conclusions

Nanoemulsions are receiving increasing attention as drug carrier

Applicable for almost all routes of delivery

Wide range of molecules can be loaded

New technology could be developed to overcome the poor absorption and miscibility of some phytopharmaceutical