Starch nanoparticles formation via high power ultrasonication.

Nano-sized starch particles (NSP) were prepared from starch granules using a purely physical method of high-intensity ultrasonication. Particle size distribution, Field Effect Scanning Electron Microscopy (FE-SEM), Raman spectroscopy, and Wide-Angle X-ray Diffraction (WAXD) were used to characterize the morphology and crystal structure of the ensuing nanoparticles. The results revealed that ultrasound treatment of the starch suspension in water and at low temperature for 75 min results in the formation of starch nanoparticles between 30 and 100 nm in size. An attempt to explain the generation of starch nanoparticles was made on the basis of WAXD, Raman analysis and FE-SEM observation. Compared to acid hydrolysis, which is the most commonly adopted process, the present approach has the advantage of being quite rapid, presenting a higher yield and not requiring any chemical treatment.