[Study on the Release Process for Lavender Essential Oil Microcapsule by FTIR].

Area of Science:

• Physical Chemistry
• Materials Science
• Spectroscopy

Background:

• Understanding the complexation and release mechanisms of active compounds from microcapsules is crucial for product development.
• Lavender essential oil (LO) and β-cyclodextrin (β-CD) form inclusion complexes with potential applications in various industries.
• Investigating the physical and chemical stability of these complexes under different conditions is essential for their practical use.

Purpose of the Study:

• To determine the constituent forms of lavender essential oil-β-cyclodextrin inclusion complexes.
• To analyze the release process of lavender essential oil from microcapsules at varying temperatures.
• To evaluate the physical and chemical stability of the encapsulated lavender essential oil.

Main Methods:

• Fourier Transform Infrared Spectroscopy (FTIR) was employed to analyze the inclusion complex formation and spectral changes.
• Principal Component Analysis (PCA) was used to interpret the infrared spectral data and assess stability and release.
• Variable temperature infrared spectroscopy was conducted across a temperature range of 25–95 °C.

Main Results:

• FTIR analysis revealed characteristic peak shifts and broadening in the embedded LO, indicating hydrogen bonding and spatial interactions within the β-CD structure.
• The microcapsules exhibited stable physical and chemical properties, with less than 6.5% LO release even at 95 °C.
• PCA analysis showed high cumulative variance (99.3%) in the first two principal components, differentiating β-CD and LO characteristics, and indicated faster ester release than alcohol release.

Conclusions:

• The formation of lavender essential oil-β-cyclodextrin inclusion complexes results in stable microcapsules with controlled release properties.
• FTIR and PCA provide an efficient method for understanding the stability and release dynamics of encapsulated essential oils.
• This research offers valuable theoretical support for the study and application of lavender essential oil microcapsules.