Stability of Curcumin on Amphiphilic Chitosan

Area of Science:

• Materials Science
• Polymer Chemistry
• Spectroscopy

Background:

• Curcumin (Cur) is a natural compound with therapeutic potential but suffers from poor stability.
• Chitosan derivatives can be synthesized to improve the properties of biomaterials.
• Understanding the interaction between Cur and modified chitosan is crucial for its application.

Purpose of the Study:

• To synthesize an amphiphilic derivative of chitosan (modified chitosan, ChM).
• To evaluate the stability of curcumin (Cur) in the presence of ChM.
• To investigate the self-assembly behavior of ChM and its effect on Cur stabilization.

Main Methods:

• Synthesis of amphiphilic chitosan derivative.
• UV-vis and fluorescence spectroscopy for stability and spectral analysis.
• Pyrene fluorescence for critical aggregation concentration (CAC) determination.
• Fluorescence microscopy for visualizing Cur localization.

Main Results:

• Modified chitosan (ChM) forms hydrophobic aggregates above 1.1 × 10⁻² g·L⁻¹.
• ChM stabilizes curcumin in its keto form, enhancing spectral characteristics.
• Curcumin fluorescence intensity and quantum yield significantly increased in ChM aggregates.
• Curcumin degradation was reduced to 30% in 0.05 g·L⁻¹ ChM, compared to 96% in buffer.

Conclusions:

• Modified chitosan (ChM) effectively stabilizes curcumin (Cur) by incorporating it into hydrophobic aggregates above its CAC.
• The aggregated ChM provides a protective environment, significantly reducing Curcumin degradation.
• This ChM-based system offers a promising approach for enhancing the stability of curcumin in aqueous formulations.