Acetylated debranched starch micelles as a promising nanocarrier for curcumin

Natural amphiphilic polymer micelles are of great interest as a carrier of hydrophobic functional ingredients due to their relatively easy synthesis, biocompatibility, and extensive sources. This study modified debranched starch (DBS) with acetic anhydride to introduce the hydrophobic acetyl group, and micelles were then obtained through the self-assembly of acetylated debranched starch (ADBS). The degree of substitution (DS) and the structural and thermal properties of ADBS were systematically investigated; the maximum DS value was 0.17. Proton nuclear magnetic resonance spectra of ADBS confirmed the presence of acetyl methyl protons, and Fourier transform infrared spectra exhibited a new absorption band of carbonyl C = O vibration at 1730 cm−1 due to the introduction of acetyl. The developed micelles were mostly spherical, and the particle size was about 50–100 nm. The critical micelle concentration was 0.45 mg/mL. Curcumin was incorporated into the micelles successfully, and the curcumin-loaded micelles exhibited sustained release properties in simulated gastric and intestinal fluids.