Preparation and characterization of starch nanoparticles via self-assembly at moderate temperature.

Starch nanoparticles (SNPs) were fabricated via short glucan chains self-assembly at 50 °C and their characteristics were evaluated by transmission electron microscopy, dynamic light scattering, molecular weight distributions, X-ray diffraction, differential scanning calorimetry, and Fourier transforms infrared spectroscopy. The results showed that SNPs exhibited spherical particles with a diameter of approximately 30-40 nm. The molecular weight of the SNPs mainly distributed at degree of polymerization (DP) 12 and DP 30. The gelatinization temperature of the SNPs increased dramatically compared to that of native waxy maize starch. The crystallinity of the samples increased as the assembling time increased and showed the same A-type in the X-ray diffraction pattern as native starch. This newly proposed SNPs approach has potential application in starch nanocomposite films due to their high gelatinization temperature.