Nanoparticle formation from amylose-fatty acid inclusion complexes prepared by steam jet cooking

Starch-based nanoparticles are of increasing interest for use as biobased fillers in composites with rubber and other polymers. Different methods have been reported for producing them, many requiring lengthy or complicated procedures. The purpose of this study was to determine whether the previously reported formation of spherulites by slowly cooling jet cooked dispersions of amylose inclusion complexes could be modified for nanoparticle synthesis. High-amylose cornstarch combined with oleic acid was jet cooked and then cooled at different rates ranging from 110 min to 10 s. Dynamic light scattering and SEM analysis showed that nanoparticles with diameters from 63 to 375 nm were obtained. X-ray diffraction analysis confirmed that they were comprised of V6 amylose complexes. Cooling rate and starch concentration affected yield of nanoparticles and their tendency to aggregate. Large quantities of starch-based nanoparticles can be prepared using this scalable method for further characterization and application development.