Study on the antibacterial mechanism of copper ion- and neodymium ion-modified α-zirconium phosphate with better antibacterial activity and lower cytotoxicity

To improve the antibacterial activity of Cu2+, a series of Cu2+ and/or Nd3+-modified layered alpha-zirconium phosphate (ZrP) was prepared and characterized, and the antibacterial activities of the prepared Cu2+ and/or Nd3+-modified ZrP on Gram-negative Escherichia coli were investigated. The results showed that the basal spacing of ZrP was not obviously affected by the incorporation of Cu2+, but the basal spacing of the modified ZrP changed into an amorphous state with increasing additions of Nd3+. An antibacterial mechanism showed that Cu2+ and Nd3+ could enter into E. coli cells, leading to changes in ion concentrations and leakage of DNA, RNA and protein. The Cu2+- and Nd3+-modified ZrP, combining the advantages of Cu2+ and Nd3+, displayed excellent additive antibacterial activity and lower cytotoxicity, suggesting the great potential application as an antibacterial powder for microbial control. Crown Copyright (c) 2015 Published by Elsevier B.V. All rights reserved.