Structure-property relationships in phenolic acid-chitosan complexes: From molecular interactions to multifunctional...

Area of Science:

• Materials Science
• Biochemistry
• Food Science

Background:

• Phenolic acid-chitosan complexes offer combined antioxidant and antibacterial benefits.
• Synthesis challenges have limited research into these complexes.
• Developing efficient synthesis methods is crucial for their application.

Purpose of the Study:

• To synthesize phenolic acid-chitosan complexes using a thermal-assisted method.
• To investigate the structure-property relationships of these complexes.
• To evaluate their potential for food preservation.

Main Methods:

• Complexation of four phenolic acids (HA, PA, VA, FA) with chitosan in aqueous medium.
• Thermal treatment to enhance solubility and complexation efficiency.
• X-ray Photoelectron Spectroscopy (XPS) for chemical analysis.
• Evaluation of thermal stability, wettability, emulsifying performance, antioxidant capacity, antibacterial activity, and cytotoxicity.

Main Results:

• Elevated temperatures improved phenolic acid solubility and complexation efficiency.
• Phenolic acid structure, particularly hydroxyl and methoxy groups, influenced bonding with chitosan.
• Complex properties (thermal stability, wettability, emulsifying, antioxidant, antibacterial) correlated with phenolic acid structure and ionic content.
• All complexes demonstrated >75% cell viability at relevant concentrations, indicating good biocompatibility.

Conclusions:

• A structure-property relationship was established, where phenolic acid substituents dictate interactions with chitosan and final complex characteristics.
• Thermal-assisted synthesis provides a simple, catalyst-free route to multifunctional phenolic acid-chitosan complexes.
• These complexes show significant potential for applications in food preservation due to their combined properties and biocompatibility.