Semi-solid Sucrose Stearate-Based Emulsions as Dermal Drug Delivery Systems

Area of Science:

• Pharmaceutical Sciences
• Materials Science

Background:

• Sucrose esters are mild non-ionic surfactants with potential in lipid-based drug delivery systems.
• Intermediate lipophilicity sucrose esters, like sucrose stearate S-970, exhibit unique rheological properties.
• These properties enable the creation of highly viscous semi-solid formulations without additional excipients.

Purpose of the Study:

• To investigate the production of lipid-based drug delivery systems using sucrose esters.
• To explore the development of both viscous macroemulsions and fluid nanoemulsions with identical chemical compositions.
• To assess the impact of formulation structure on drug release properties.

Main Methods:

• Optical light microscopy and cryo transmission electron microscopy (TEM) were used to characterize emulsion structures.
• Franz-cell diffusion studies and in vitro tape stripping were employed to evaluate drug release.
• Variations in the production process were used to generate macroemulsions and nanoemulsions.

Main Results:

• Sucrose ester at 5% w/w formed a hydrophilic network in macroemulsions.
• Nanoemulsions contained smaller aggregates of surplus surfactant.
• Drug release studies indicated no impairment despite high macroviscosity and complex internal structures in macroemulsions.

Conclusions:

• Sucrose esters facilitate the development of stable, skin-friendly O/W emulsions with desirable application properties.
• The production method is simple, rapid, and yields emulsions with excellent long-term visual stability.
• These lipid-based emulsions are suitable for effective delivery of lipophilic drugs, even with high viscosity and larger particle sizes.