Research progress on protein-based unary, binary, and ternary encapsulation systems: A review

Protein-based encapsulation systems have emerged as vital delivery carriers due to their unique structural and functional properties. This review systematically introduces protein-based encapsulation systems, with a focus on the fundamental characteristics, interaction mechanisms, and encapsulation methods of unary, binary, and ternary systems. These systems regulate the loading and release of active compounds through covalent and non-covalent interactions, requiring a rational balance of crosslinking degrees and interaction forces to optimize carrier performance. Although the interaction mechanisms in unary systems, based on single proteins, are relatively straightforward, these systems are often limited by low loading capacity and insufficient responsiveness to environmental stimuli. Binary systems significantly improve the stability and loading efficiency of carriers through the synergistic interactions between multiple components. Ternary systems further enhance multiphase interfacial interactions, leading to improved sustained release behavior. However, protein-based encapsulation systems still face challenges, such as complex manufacturing processes and limited environmental adaptability, and their mechanism of action needs to be studied in depth in the future. This study provides a theoretical foundation for understanding intermolecular interaction mechanisms in encapsulation technologies and supports the optimized design of functional composite systems.