Easy and Effective Method for α-CD:N₂O Host-Guest Complex Formation.

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Chemical Engineering

Background:

• Cyclodextrins (CDs) are known for their ability to form inclusion complexes.
• Nitrous oxide (N₂O) has applications in food and beverages, requiring stable storage methods.

Purpose of the Study:

• To investigate the formation and N₂O storage capacity of alpha-cyclodextrin (α-CD):N₂O complexes.
• To compare a novel solid-gas reaction method with traditional crystallization for N₂O inclusion.

Main Methods:

• Solid-gas reaction: N₂O sorption into α-CD under varying pressures and temperatures.
• Comparison with crystallization method from aqueous α-CD solutions saturated with N₂O.
• Analysis of N₂O binding modes and complex stability.

Main Results:

• Maximum N₂O storage capacity of 4.5 wt.% achieved via gas phase charging.
• Storage capacity decreased to 1.3 wt.% upon storage in air at ambient conditions.
• External coordination of N₂O to α-CD rims, involving hydrogen bonds and hydration water, was identified as the preferred binding mode.

Conclusions:

• The solid-gas reaction offers a more efficient method for N₂O inclusion into α-CD.
• The α-CD:N₂O complexes exhibit promising thermal stability for potential applications.
• These findings suggest viable applications in the food and beverage industries for N₂O storage.