Production of tapioca starch nanoparticles by nanoprecipitation-sonication treatment.

In this study tapioca starch nanoparticles (SNPs) were prepared by nanoprecipitation with acetone and nanoprecipitation-sonication treatments. The prepared SNPs were characterized by dynamic light scattering (DLS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR). The results revealed that application of ultrasound not only increased the yield but also decreased the acetone consumption. Electron micrographs indicate that all SNPs were spherical in shape while having different particle size. Samples prepared using 3 g starch by sonication treatment had relatively similar particle size as those prepared using 1 g starch with no sonication. The increase in starch concentration, increased the particle size of samples and the samples with the highest concentration of starch had the largest particle size. The crystalline structure of native starch was destroyed by nanoprecipitation and sonication. The lowest sample crystallinity was realized for SNPs prepared by nanoprecipitation and sonication of 1 g starch. The DSC data showed that the thermal properties of SNPs were lower than those of native starch. The FT-IR spectroscopy exhibited slight changes between native starch and SNPs.