title: Analysis of copper nanoparticles toxicity based on a stress-responsive bacterial biosensor array.
abstract: The rapid development in nanoparticle production and application during the past decade requires an easy, rapid, and predictive screening method for nanoparticles toxicity assay. In this study, the toxicological effects and the source of toxicity of copper nanoparticles (CuNPs) are investigated based on a stress-responsive bacterial biosensor array. According to the responses of the biosensing strains, it is found that CuNPs induce not only oxidative stress in E. coli, but also protein damage, DNA damage, and cell membrane damage, and ultimately cause cell growth inhibition. Through enzyme detoxification analysis, the toxicological effects of CuNPs are traced to H(2)O(2) generation from CuNPs. Rapid copper release from CuNPs and Cu(I) production are observed. The oxidation of the released Cu(I) has a close relation to H(2)O(2) production, as tris-(hydroxypropyltriazolylmethyl) amine, the specific Cu(I) chelator, can largely protect the cells from the toxicity of CuNPs. In addition, the TEM study shows that CuNPs can be adsorbed and incepted fast by the cells. Comparatively, copper microparticles are relatively stable in the system and practically non-toxic, which indicates the importance of toxic estimation of materials at the nanoscale. In addition, the Cu(II) ion can induce protein damage, membrane damage, and slight DNA damage only at a relatively high concentration. The current study reveals the preliminary mechanism of toxicity of CuNPs, and suggests that the stress-responsive bacterial biosensor array can be used as a simple and promising tool for rapid screening in vitro toxicity of nanoparticles and studying the primary mechanism of the toxicity.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, PR China.
authors.forename: Fenfang
authors.initials: F
authors.lastname: Li
authors.forename: Chunyang
authors.initials: C
authors.lastname: Lei
authors.forename: Qinpeng
authors.initials: Q
authors.lastname: Shen
authors.forename: Lijun
authors.initials: L
authors.lastname: Li
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
authors.forename: Manli
authors.initials: M
authors.lastname: Guo
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.forename: Zhou
authors.initials: Z
authors.lastname: Nie
authors.forename: Shouzhuo
authors.initials: S
authors.lastname: Yao
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D015374:Biosensing Techniques; D002462:Cell Membrane / Q000378:metabolism; D003300:Copper / Q000737:chemistry* / Q000378:metabolism; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000737:chemistry; D007477:Ions; D053768:Metal Nanoparticles / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning / Q000379:methods; D046529:Microscopy, Electron, Transmission / Q000379:methods; D008954:Models, Biological; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods; D010316:Particle Size; D014961:X-Ray Diffraction / Q000379:methods
chemical_list: D007477:Ions; D003300:Copper; D006861:Hydrogen Peroxide