Tunable Rheological Properties and Controlled Curcumin Release in Pickering Emulsions Stabilized by Self-Assembled Chitosan Particles

The rational design of functional soft materials requires precise control over colloidal assembly and interfacial interactions. Here, we report a simple pH-responsive strategy to fabricate self-assembled chitosan colloids that act as efficient particle stabilizers for Pickering emulsions without chemical modification or additional particle fabrication steps. By tailoring the self-assembly process, the colloidal particles exhibited tunable surface charge, wettability, aggregation state, and interfacial adsorption, enabling the formation of stable oil–water interfaces. The resulting Pickering emulsions displayed distinct microstructures and tunable viscoelastic behavior arising from particle-network formation in the continuous phase. Rheological measurements demonstrated enhanced elasticity and structural integrity associated with stronger colloidal interactions, while temperature-dependent experiments revealed reversible structural evolution governed by hydrogen-bond-mediated assembly. The engineered colloidal interfaces also provided effective encapsulation of curcumin, improving loading capacity, physical stability, and sustained release compared with less structured systems. Correlating particle self-assembly with interfacial organization, rheological response, and encapsulation performance establishes clear structure–property relationships in these soft colloidal materials. This work demonstrates that pH-directed molecular assembly of chitosan offers a sustainable and versatile platform for engineering functional colloidal interfaces and responsive Pickering emulsions. The findings provide new insights into the design of biopolymer-based soft materials for controlled delivery, food colloids, pharmaceutical formulations, and other advanced interfacial applications. The abstract is based on the reported study and reframes its emphasis toward colloidal self-assembly, interfaces, rheology, and functional soft materials.