Procyanidins-Loaded Complex Coacervates for Improved Stability by Self-Crosslinking and Calcium Ions Chelation

The purpose of this work was to develop a facile strategy based on self-crosslinking between the core and wall materials in the coacervation system for effective procyanidins (PCs) encapsulation. The coacervates were constructed through the interaction of bioactive PCs, gelatin, and sodium alginate, followed by forming cationic bridge of sodium alginate-calcium ions to improve the stability of PCs. When the concentration of PCs and calcium ions were 6.25 and 0.24 mg/mL, respectively, the PC-loaded coacervates showed spherical shape with a size about 150 nm, and the microcapsulation efficiency and yield was 81.19 +/- 1.47 and 87.86 +/- 2.67%, respectively. The photothermal stability of PCs was effectively improved by embedding them in coacervates. The decrease of mitochondrial membrane potential in PC-12 cells induced by H2O2 was significantly inhibited by PC coacervates, demonstrating an improved protection effect of PCs after being encapsulated in coacervates.