Pickering emulsions with α-cyclodextrin inclusions: Structure and thermal stability

Area of Science:

• Colloid and Surface Science
• Materials Science
• Supramolecular Chemistry

Background:

• Pickering emulsions offer enhanced stability through solid particle stabilization.
• Alpha-cyclodextrin inclusion complexes provide tunable properties for emulsion formulation.
• Understanding interfacial phenomena is crucial for designing advanced emulsion systems.

Purpose of the Study:

• To explore the structural, interfacial, and thermal properties of Pickering emulsions stabilized by alpha-cyclodextrin inclusion complexes.
• To investigate the influence of oil molecular architecture on emulsion characteristics.
• To analyze the thermal behavior and interfacial interactions within these complex emulsion systems.

Main Methods:

• Microcalorimetry for thermal analysis.
• X-ray diffraction for structural characterization.
• Confocal microscopy for visualizing interfacial properties.

Main Results:

• Emulsion properties varied significantly based on the molecular structure of different oils (fatty acids, olive oil, silicone oil).
• The ability of oil molecules to form inclusion complexes with alpha-cyclodextrin was critical for emulsification and thermal stability.
• Inclusion complexes exhibited progressive dissolution and melting above 100°C.
• Partial guest molecule substitution at oil/water interfaces was observed at room temperature in emulsions containing micro-platelets.

Conclusions:

• The molecular architecture of oils and their interaction with alpha-cyclodextrin dictate Pickering emulsion stability and thermal behavior.
• Interfacial substitution mechanisms can influence the properties of emulsions even at ambient temperatures.
• These findings provide insights into the design of novel functional emulsions for various applications.