Interacted With B.subtilis By Nano-rod CeO₂:Mechanisms And Inspiration

With the rapid development of nanotechnology and its broad applications, a large accounts of engineered nanoparticles?NPs? are now used in industries, biomedical products and commodities in this 21 centuries. As the La group elements, because of their unique physicochemical properties, such as highly reactivity, Their NPs have raised concerns about the potential biological effects. However, the biological effects of nano-Ce O₂ are still controversial.In this article, we investigate the biological effects of nano-rod Ce O₂ by using Bacillus subtilis?B. subtilis?, what wants to know is the potential toxicity mechanism about nano-rod Ce O₂ to B. subtilis. To use the ions, nanoparticles and the different media to know what caused the toxicity to B. subtilis.The main tasks are given as follows:Sythesised of nano-Ce O₂ with different shapes and sizes; We succeeded in synthesis the uniform nano-Ce O₂ with shape and size controlled using the hydrothermal and precipitation.We obtained the nano-rod Ce O₂ with uniform strcutrues, and obtained the different shape and size of 25 nm by using precipitation methods.Chosen the four patterns: Escherichia coli, Pseudomonas putida, Staphylococcus aureus and Bacillus subtilis, all of the above tested bacteria were different species to use to investigate the synthetic of ceria nanoparticles transformation abilities.The results was detailed as follows: whatever the 4 different species were all failed for 25 nm ceria transformation, but B. subtilis and S. aureus could cause the different degreed of the transformation of the nano-rod ceria.The toxicities and mechanisms of nano-rod ceria and ions to B. subtilis were explored.The toxicity of nano-rod ceria were mainly from the ions.The Ce³⁺ ions occupy a major role in this toxicity effect. With the different medium?LB and K-medium?, which had a great different influence on its toxicity.The different concentration of nano-rod ceria and ions were investigated to understand what is the relationship between the nanomaterials/ions and the biofilm, which was during the growing period or mature one. The conclusion is: with the increment of concentration of nanomaterials, the biomass of biological membrane and membrane formation have obvious inhibitory effect. Extracellular polymer was secreted by bacterial, which have have the relief protection effect for biofilms to against the nanomaterials and ions' destruction.