Abstract
In nature, the assembly of biomolecules (e.g., saccharides, protein) spontaneously occurs in water into highly ordered compartmentalized hollow architecture such as cells. Cell-mimetic compartmentalized saccharide nanocapsules have emerged as important colloidal materials with great utility in the pharmaceutical and food fields. However, it remains challenging to fabricate hollow nanocapsules using highly hydrophilic natural saccharides in water. Herein, we report on the one-pot fabrication of hollow nanocapsules through a two-stepwise interfacial hydrogen bonding reorganization-assisted aqueous assembly of thermo-responsive hydroxypropyl cellulose (HPC) with pH-sensitive curcumin. A first-step solution mixing-triggered pH/temperature shifting significantly weakens the hydrogen bonding interaction of HPC with water molecules and leads to the protonation of curcumin, simultaneously driving supersaturation-induced phase separation and ordered co-aggregation in aqueous solution. A second-step temperature shifting rapidly rebuilds hydrogen bonding between HPC and curcumin at their interface to stabilize curcumin-entrapped amphiphilic nanostructures, robustly generating hollow nanocapsules with high loading capacity (up to 44 %) and good colloidal stability. The careful establishment of phase diagrams provides the conditions for producing nanocapsules under which the particle sizes, compositions and loading capacities can be regulated conveniently. The versatility of approach enables robust construction of compartmentalized polysaccharide nanomaterials with well-customized properties and functions, showing considerable potential in various fields.