Effects of Different TiO2 Nanoparticles Concentrations on the Physical and Antibacterial Activities of Chitosan-Based Coating Film

Yage Xing; Xuanlin Li; Xunlian Guo; Wenxiu Li; Jianwen Chen; Qian Liu; Qinglian Xu; Qin Wang; Hua Yang; Yuru Shui; Xiufang Bi

doi:10.3390/nano10071365

Effects of Different TiO₂ Nanoparticles Concentrations on the Physical and Antibacterial Activities of Chitosan-Based Coating Film

Nanomaterials (Basel). 2020 Jul 13;10(7):1365. doi: 10.3390/nano10071365.

Authors

Yage Xing¹, Xuanlin Li¹, Xunlian Guo^{1

2}, Wenxiu Li¹, Jianwen Chen¹, Qian Liu^{1

3}, Qinglian Xu¹, Qin Wang³, Hua Yang¹, Yuru Shui^{1

4}, Xiufang Bi¹

Affiliations

¹ Key Laboratory of Grain and Oil Engineering and Food Safety of Sichuan Province, College of Food and Bioengineering, Xihua University, Chengdu 610039, China.
² Department of Food Science and Engineering, College of Landscape Architecture, Shangqiu University, Shangqiu 476000, China.
³ Department of Nutrition and Food Science, Maryland University, College Park, MD 20742, USA.
⁴ Key Laboratory of Food Non-Thermal Technology, Engineering Technology Research Center of Food Non-Thermal, Yibin Xihua University Research Institute, Yibin 644004, China.

Abstract

In this investigation, the effect of different concentrations of titanium dioxide (TiO₂) nanoparticles (NPs) on the structure and antimicrobial activity of chitosan-based coating films was examined. Analysis using scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed that the modified TiO₂ NPs were successfully dispersed into the chitosan matrix, and that the roughness of the chitosan-TiO₂ nanocomposites were significantly reduced. Moreover, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses indicated that the chitosan interacted with TiO₂ NPs and possessed good compatibility, while a thermogravimetric analysis (TGA) of the thermal properties showed that the chitosan-TiO₂ nanocomposites with 0.05% TiO₂ NPs concentration had the best thermal stability. The chitosan-TiO₂ nanocomposite exhibited an inhibitory effect on the growth of Escherichia coli and Staphylococcus aureus. This antimicrobial activity of the chitosan-TiO₂ nanocomposites had an inhibition zone ranging from 9.86 ± 0.90 to 13.55 ± 0.35 (mm). These results, therefore, indicate that chitosan-based coating films incorporated with TiO₂ NPs might become a potential packaging system for prolonging the shelf-life of fruits and vegetables.

Keywords: TiO2; antimicrobial activity; chitosan-based coating/film; physicochemical characterization.