Black rice anthocyanins embedded in self-assembled chitosan/chondroitin sulfate nanoparticles enhance apoptosis in HCT-116 cells.

Self-assembled nanoparticles using the biopolymers chitosan (CH) and chondroitin sulfate (CS) were developed to improve the biological activity of anthocyanin (ACN). The 86.32 ± 0.15% (w/w) of ACN was incorporated into ACN/CH/CS nanoparticles, with the particle size of 350.1 ± 0.99 nm in diameter (i.d.) and 42.55 ± 0.54 in zeta potential (mV). Morphological study and thermogravimetric analysis suggested that the ACN/CH/CS nanoparticles exhibited heterogeneous morphology and high thermal stability. Significant increases in apoptosis by 12.1% and 35.1% were observed with 0.05 mg/ml ACN and ACN/CH/CS nanoparticles in the HCT-116 cell line, indicating that the nanoparticle system led to significant increase in apoptosis (p < 0.05). Structural changes in mitochondria caused by ACN/CH/CS nanoparticles indicated that the nanoparticles had negative impacts on mitochondria. These results showed that nanoparticles could potentially be used as a carrier system to improve the efficacy of ACN.