Self-assembly mechanism of ferritin/aminated gelatin colloid nanoparticles and its application for the fabrication of stable compartmentalized emulsions: The key role of mixing ratio and dropwise manner

The construction of stable dual-compartmental structures is crucial for co-encapsulation and delivery of food nutrients. Herein, we explored the self-assembly beheavior and mechanism of ferritin (Fn) and aminated gelatin (AGEL), aiming to construct stable Fn/AGEL dual-compartment emulsions. Interestingly, as the AGEL concentration increased, the particle size of Fn/AGEL assemblies inversely decreased from micro- scale to nano-scale. Furthermore, the mixing dropwise manner significantly affects the size distribution of Fn/AGEL assemblies. Multiple analysis revealed that electrostatic attractions were the main chemical force driving their assembly, and both ratio and dropwise manner seem to affect the initial Fn/AGEL nucleus, ultimately altering their properties and structures. Besides, Fn/AGEL particles exhibit a reversible assembly and disassembly beheavior. Finally, stable dual-compartment emulsions with superior properties are constructed with dropwise manner of adding Fn to AGEL solution at 1:1 ratio. Overall, these findings can facilitate the development and application of ferritin-based dual-compartment emulsions.