Solid-stabilized emulsions - UMR CNRS 8612 Institut Galien Paris

Séminaire de l’UMR CNRS 8612
jeudi 30 avril 2009, salle EH25
de 13 à 14h
Solid-stabilized emulsions: physical chemistry studies and
application to skin drug delivery
Justyna Frelichowska
UMR CNRS 8612
Equipe « Amélioration du passage des barrières par les molécules biologiquement actives »
The stabilization of emulsions can be realized using the solid particles instead of emulsifier
molecules. Solid-stabilized emulsions are called also “the Pickering emulsions”.
The aims of the presented work are:
1) to investigate the physical chemistry aspects of these emulsions;
2) to evaluate them for the skin drug delivery for the first time.
The emulsions were stabilized with fumed silica nanoparticles within a range of hydrophobic
- hydrophilic properties. The oil-in-water emulsions obtained with partially hydrophobic silica
were characterized in the terms of stability, rheology and optimal particle quantity necessary
for emulsion stabilization. The role of particle aggregation caused by oil and by electrolytes in
emulsion stabilisation was emphasized. The oil-in-water emulsion stabilisation using
completely hydrophilic silica particles was possible only with very polar oils (Frelichowska et
al., pending patent; Frelichowska et al., Colloids and Surfaces A, in press).
The second part of the studies concerns the evaluation of solid-stabilized emulsions in the
terms of drug delivery to the skin, comparing them to the classical surfactant-stabilized
systems. The oil-in-water and water-in-oil emulsions with model active ingredients (retinol as
lipophilic molecule and caffeine as hydrophilic molecule) were prepared and formulations
were optimized. The delivery of drugs to the skin was significantly different for solidstabilized and surfactant stabilized systems (Frelichowska et al., Int J Pharm 368(1-2):7-15
and Int J Pharm 371(1-2):56-63). Pickering emulsions can be considered as a potential
formulation for topical drug delivery.
Renseignements : Vincent FAIVRE (45465), [email protected]
Julien NICOLAS (45853), [email protected]