Preparation and antibacterial properties of titanium-doped ZnO from different zinc salts

Tong Sun,Shu-Min Yi,Wen-Ting Hao,Xue-Peng Li,Jian-Rong Li,Han Hao

doi:10.1186/1556-276x-9-98

Abstract

To research the relationship of micro-structures and antibacterial properties of the titanium-doped ZnO powders and probe their antibacterial mechanism, titanium-doped ZnO powders with different shapes and sizes were prepared from different zinc salts by alcohothermal method. The ZnO powders were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED), and the antibacterial activities of titanium-doped ZnO powders on Escherichia coli and Staphylococcus aureus were evaluated. Furthermore, the tested strains were characterized by SEM, and the electrical conductance variation trend of the bacterial suspension was characterized. The results indicate that the morphologies of the powders are different due to preparation from different zinc salts. The XRD results manifest that the samples synthesized from zinc acetate, zinc nitrate, and zinc chloride are zincite ZnO, and the sample synthesized from zinc sulfate is the mixture of ZnO, ZnTiO3, and ZnSO4 · 3Zn (OH)2 crystal. UV-vis spectra show that the absorption edges of the titanium-doped ZnO powders are red shifted to more than 400 nm which are prepared from zinc acetate, zinc nitrate, and zinc chloride. The antibacterial activity of titanium-doped ZnO powders synthesized from zinc chloride is optimal, and its minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) are lower than 0.25 g L−1. Likewise, when the bacteria are treated by ZnO powders synthesized from zinc chloride, the bacterial cells are damaged most seriously, and the electrical conductance increment of bacterial suspension is slightly high. It can be inferred that the antibacterial properties of the titanium-doped ZnO powders are relevant to the microstructure, particle size, and the crystal. The powders can damage the cell walls; thus, the electrolyte is leaked from cells.

Highlights

Antibacterial agents are applied to many fields, such as food [1,2], care [3], packaging [4], synthetic textiles [5], environmental [6], and so on
The peaks of titanium-doped ZnO powders synthesized from zinc nitrate and zinc chloride are sharper than others, and the half peak width is narrower
The antibacterial property results show that the titanium-doped ZnO powders against E. coli is better than S. aureus, the scanning electron microscopy (SEM) characterizations of the bacterial cells indicate that the powders make the cell wall damage, and the electrical conductance analytic results demonstrate that the electrical conductance added values of E. coli suspension are slightly higher than that of S. aureus suspension after treatment with the powders

Summary

Introduction

Antibacterial agents are applied to many fields, such as food [1,2], care [3], packaging [4], synthetic textiles [5], environmental [6], and so on. Chemical synthesis antibacterial agent is divided into two categories: organic and inorganic antibacterial agent [7,8,9]. Organic antibacterial agent has many disadvantages, including the toxicity hazard to the human body and instability in high temperature and pressure [10]. Inorganic antibacterial agent has the properties of heat resistance, long life, and chemical stability [11]. Metallic simple substances and their compounds are used widely technology in synthetic material. Using this method, the crystal grain can develop completely and the particle size is uniform

Methods

Results

Discussion

Conclusion