Starch nanoparticles preparation and characterization by in situ combination of sono-precipitation and alkali hydrolysis under ambient temperature

The current work aimed at adopting in situ combination of sono-precipitation and alkali hydrolysis as a rapid technique for starch nanoparticles (SNPs) preparation under ambient conditions with a high yield. Factors affecting the preparation of SNPs were investigated based on statistical analysis using the Box Behnken design. The particle size and polydispersity index of particles were used as dependent variables to obtain the optimized formulation. The SNPs optimized formulation (F14) was further characterized for zeta potential, transmission electron microscopy, Fourier transform infrared spectroscopy, differential thermal analysis and X-ray diffraction. The results of particle size were between 44.82±3.31 and 83.93±8.53 while polydispersity index results were ranged from 0.106±0.012 to 0.179±0.018. The results obtained revealed the efficiency of the technique in obtaining a high yield (98.72% ±0.89) of well-distributed nanoparticles. Also, the SNPs obtained were spherical in shape with good stability, as indicated by zeta analysis (−20±0.25mV) and thermal analysis. The data obtained also showed no change in the chemical structure of the SNPs, as indicated by the infrared transmission of Fourier, thermal analysis, and the relative crystallinity of SNPs was decreased compared with native maize starch indicating the crystallite is transformed from crystalline to amorphous form. The obtained results concluded the efficiency of the adopted method on obtaining SNPs in a short preparation time with a high yield under ambient conditions.