Surface Chemical Compositions and Dispersity of Starch Nanocrystals Formed by Sulfuric and Hydrochloric Acid Hydrolysis

• Published in: PloS one Vol. 9; no. 2; p. e86024
• Main Authors: Wei, Benxi, Xu, Xueming, Jin, Zhengyu, Tian, Yaoqi
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 27.02.2014; Public Library of Science (PLoS)
• Subjects: Acids; Agriculture; Biology; Cellulose; Change detection; Chemical composition; Chemistry; Crystals; Esters; Food safety; Food science; Fourier transforms; Hydrochloric acid; Hydrochloric Acid - chemistry; Hydrogen ions; Hydrolysis; Infrared spectroscopy; Laboratories; Lipids; Materials Science; Nanocrystals; Nanoparticles - chemistry; Nanoparticles - ultrastructure; Nutrition; Particle size distribution; pH effects; Photoelectron Spectroscopy; Photoelectrons; Polymer blends; Polyvinyl alcohol; Potassium; Reagents; Size distribution; Spectroscopy; Spectroscopy, Fourier Transform Infrared; Spectrum analysis; Starch; Starch - chemistry; Sulfate; Sulfates; Sulfuric acid; Sulfuric Acids - chemistry; X ray photoelectron spectroscopy; X-ray spectroscopy; Zeta potential; China
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0086024

Surface chemical compositions of starch nanocrystals (SNC) prepared using sulfuric acid (H2SO4) and hydrochloric acid (HCl) hydrolysis were analyzed by X-ray photoelectron spectroscopy (XPS) and FT-IR. The results showed that carboxyl groups and sulfate esters were presented in SNC after hydrolysis with H2SO4, while no sulfate esters were detected in SNC during HCl-hydrolysis. TEM results showed that, compared to H2SO4-hydrolyzed sample, a wider size distribution of SNC prepared by HCl-hydrolysis were observed. Zeta-potentials were -23.1 and -5.02 mV for H2SO4- and HCl-hydrolyzed SNC suspensions at pH 6.5, respectively. Nevertheless, the zeta-potential values decreased to -32.3 and -10.2 mV as the dispersion pH was adjusted to 10.6. After placed 48 h at pH 10.6, zeta-potential increased to -24.1 mV for H2SO4-hydrolyzed SNC, while no change was detected for HCl-hydrolyzed one. The higher zeta-potential and relative small particle distribution of SNC caused more stable suspensions compared to HCl-hydrolyzed sample.