title: A comparative ecotoxicity analysis of α- and γ-phase aluminium oxide nanoparticles towards a freshwater bacterial isolate Bacillus licheniformis.
abstract: Crystalline structure of nanoparticles may influence their physicochemical behaviour as well as their toxicological impact on biota. The differences in orientation of the atoms result in the variations in chemical stability. Thus, toxicological impacts of different crystalline phases of aluminium oxide nanoparticles are expected to vary. The present study brings out a comparative toxicity analysis of γ-phase and α-phase aluminium oxide nanoparticles of comparable hydrodynamic size range towards a freshwater bacterial isolate Bacillus licheniformis at low exposure concentrations (5, 1, 0.5 and 0.05 µg/mL). Upon 2-h exposure, the α-aluminium oxide particles showed lower toxicity than the γ-phase aluminium oxide. The lower level of oxidative stress generation and cell membrane damage in case of the α-phase aluminium oxide nanoparticles substantiated the toxicity results. The involvement of protein, lipopolysaccharides in nanoparticle-cell surface interaction, was noted in both the cases. To conclude, the crystallinity of aluminium oxide nanoparticles played an important role in the interaction and the toxicity response.
authors.affiliation: Centre for Nanobiotechnology, VIT University, Vellore, 632014, India.
authors.forename: Sunandan
authors.initials: S
authors.lastname: Pakrashi
authors.forename: Deepak
authors.initials: D
authors.lastname: Kumar
authors.forename: V
authors.initials: V
authors.lastname: Iswarya
authors.forename: M
authors.initials: M
authors.lastname: Bhuvaneshwari
authors.forename: N
authors.initials: N
authors.lastname: Chandrasekaran
authors.forename: Amitava
authors.initials: A
authors.lastname: Mukherjee
mesh_terms: D000537:Aluminum Oxide / Q000633:toxicity*; D001407:Bacillus / Q000187:drug effects*; D002462:Cell Membrane / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005618:Fresh Water; D007477:Ions; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008027:Light; D053768:Metal Nanoparticles / Q000633:toxicity*; D036103:Nanotechnology; D018384:Oxidative Stress; D010316:Particle Size; D017382:Reactive Oxygen Species / Q000378:metabolism; D012542:Scattering, Radiation; D017550:Spectroscopy, Fourier Transform Infrared; D018675:Toxicity Tests; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D014961:X-Ray Diffraction
chemical_list: D007477:Ions; D017382:Reactive Oxygen Species; D014874:Water Pollutants, Chemical; D007770:L-Lactate Dehydrogenase; D000537:Aluminum Oxide