title: Synthesis, characterization and toxicological evaluation of a core-shell copper oxide/polyaniline nanocomposite.
abstract: The newest generation of copper oxide NPs (CuO NPs) is the CuO core-shell (CS), which has potential applications in several areas (e.g., electronics and paint) and is able to provide a greater service life due to its coating; however, its toxicity is not fully understood. The objective of this study was to synthesize, characterize and evaluate the aquatic toxicology of CuO NPs and CuO core-shells through acute and chronic toxicity tests with the freshwater microcrustaceans Daphnia magna and to evaluate its acute toxicity with the marine bioluminescent bacteria Vibrio fischeri. The NPs were synthesized by direct thermal decomposition after being coated as a CS with polyaniline (PANI). With respect to acute toxicity with D. magna, the CuO NPs and CS CuO/PANI presented EC50 values of 0.32 mg L(-1) and 0.48 mg L(-1), respectively. For the tests with V. fischeri, the CuO NPs (EC50-15 min=7.79 mg L(-1)) exhibited behavior similar to that of the CS CuO/PANI (EC50-15 min=9.05 mg L(-1)) after 15 min of exposure. Regarding chronic toxicity, both forms showed a statistically significant effect (p<0.05) on the growth and reproduction parameters. Based on the characterization and toxicity results, it can be concluded that both forms of CuO were toxic and presented similar behaviors during the acute tests; however, after 21 d of exposure, CS CuO/PANI showed higher toxicity to the reproduction parameter, highlighting the importance of a complete study of the NP to better understand its toxicity mechanism.
authors.affiliation: Laboratório de Toxicologia Ambiental, LABTOX, Departamento de Engenharia Sanitária e Ambiental, Universidade Federal de Santa Catarina, Campus Universitário, CEP: 88040-970, Florianópolis, SC, Brazil.
authors.forename: Ana Letícia de O F
authors.initials: AL
authors.lastname: Rossetto
authors.affiliation: Laboratório de Toxicologia Ambiental, LABTOX, Departamento de Engenharia Sanitária e Ambiental, Universidade Federal de Santa Catarina, Campus Universitário, CEP: 88040-970, Florianópolis, SC, Brazil.
authors.forename: Denice S
authors.initials: DS
authors.lastname: Vicentini
authors.affiliation: Laboratório de Toxicologia Ambiental, LABTOX, Departamento de Engenharia Sanitária e Ambiental, Universidade Federal de Santa Catarina, Campus Universitário, CEP: 88040-970, Florianópolis, SC, Brazil.
authors.forename: Cristina H
authors.initials: CH
authors.lastname: Costa
authors.affiliation: Laboratório de Toxicologia Ambiental, LABTOX, Departamento de Engenharia Sanitária e Ambiental, Universidade Federal de Santa Catarina, Campus Universitário, CEP: 88040-970, Florianópolis, SC, Brazil.
authors.forename: Silvia P
authors.initials: SP
authors.lastname: Melegari
authors.affiliation: Laboratório de Toxicologia Ambiental, LABTOX, Departamento de Engenharia Sanitária e Ambiental, Universidade Federal de Santa Catarina, Campus Universitário, CEP: 88040-970, Florianópolis, SC, Brazil. Electronic address: william.g.matias@ufsc.br.
authors.forename: William G
authors.initials: WG
authors.lastname: Matias
mesh_terms: D048908:Aliivibrio fischeri / Q000187:drug effects* / Q000502:physiology; D000814:Aniline Compounds / Q000737:chemistry / Q000633:toxicity*; D000818:Animals; D003300:Copper / Q000737:chemistry / Q000633:toxicity*; D003621:Daphnia / Q000187:drug effects* / Q000502:physiology; D053761:Nanocomposites / Q000737:chemistry / Q000633:toxicity* / Q000648:ultrastructure; D012098:Reproduction / Q000187:drug effects; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity*
chemical_list: D000814:Aniline Compounds; D014874:Water Pollutants, Chemical; C416807:polyaniline; D003300:Copper; C000520:cuprous oxide
keywords: Core–shell; CuO nanoparticle; Daphnia magna; Nanotoxicology; Polyaniline; Vibrio fischeri