Influence of Precipitation Conditions on Crystallinity of Amylose Nanoparticles.

Yan, Xiaoxia; Chang, Yanjiao; Wang, Qian; Fu, Youjia; Ren, Lili; Zhou, Jiang

Amylose nanoparticles are prepared via precipitation by dropping absolute ethanol into amylose paste. X‐ray diffraction analysis reveales that the amylose nanoparticles display V‐type crystalline structure, and crystallinity of the amylose nanoparticles is dependent upon precipitation conditions, that is, temperature of amylose paste, ethanol dropping rate, and length of amylose chains. Dropping ethanol of 20 °C into amylose paste of 90 °C at a rate of 5 mL min−1 promotes the molecular association of amylose and ethanol into a helical complex and forms more amylose single helices in the precipitated amylose nanoparticles, which results in a higher crystallinity (60.72%) after the amylose nanoparticles are dried at 4 °C for 12 h and then at 40 °C for 12 h under 11% relative humidity. Shorter amylose chains may be unfavorable to complex formation between amylose and ethanol. The findings of this study provide a guideline to prepare amylose nanoparticles with higher crystallinity via precipitation.

PRECIPITATION (Chemistry); CRYSTALLINITY; AMYLOSE; NANOPARTICLES; X-ray diffraction

Starch / Staerke, 2018, Vol 70, Issue 7/8, p1

0038-9056

Academic Journal

10.1002/star.201700213