Toxicity of single-wall carbon nanotubes functionalized with polyethylene glycol in zebrafish (Danio rerio) embryos.
Single-wall carbon nanotubes functionalized with polyethylene glycol (SWCNT-PEG) are promising materials for biomedical applications such as diagnostic devices and controlled drug-release systems. However, several questions about their toxicological profile remain unanswered. Thus, the aim of this study was to investigate the action of SWCNT-PEG in Danio rerio zebrafish embryos at the molecular, physiological and morphological levels. The SWCNT used in this study were synthesized by the high-pressure carbon monoxide process, purified and then functionalized with distearoyl phosphatidylethanolamine block copolymer-PEG (molecular weight 2 kDa). The characterization process was carried out with low-resolution transmission electron microscopy, thermogravimetric analysis and Raman spectroscopy. Individual zebrafish embryos were exposed to the SWCNT-PEG. Toxic effects occurred only at the highest concentration tested (1 ppm) and included high mortality rates, delayed hatching and decreased total larval length. For all the concentrations tested, the alkaline comet assay revealed no genotoxicity, and Raman spectroscopy measurements on the histological slices revealed no intracellular nanotubes. The results shown here demonstrate that SWCNT-PEG has low toxicity in zebrafish embryos, but more studies are needed to understand what mechanisms are involved. However, the presence of residual metals is possibly among the primary mechanisms responsible for the toxic effects observed, because the purification process was not able to remove all metal contamination, as demonstrated by the thermogravimetric analysis. More attention must be given to the toxicity of these nanomaterials before they are used in biomedical applications. Copyright © 2016 John Wiley & Sons, Ltd.
Laboratório de Neurociências / Programa de Pós Graduação em Ciências Fisiológicas - Fisiologia Animal Comparada, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande - FURG, Rio Grande, RS, 96210-900, Brazil.
Felipe A
FA
Girardi
Laboratório de Neurociências / Programa de Pós Graduação em Ciências Fisiológicas - Fisiologia Animal Comparada, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande - FURG, Rio Grande, RS, 96210-900, Brazil.
Gisele E
GE
Bruch
Laboratório de Neurociências / Programa de Pós Graduação em Ciências Fisiológicas - Fisiologia Animal Comparada, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande - FURG, Rio Grande, RS, 96210-900, Brazil.
Carolina S
CS
Peixoto
Laboratório de Neurociências / Programa de Pós Graduação em Ciências Fisiológicas - Fisiologia Animal Comparada, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande - FURG, Rio Grande, RS, 96210-900, Brazil.
Lidiane
L
Dal Bosco
Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
Sangram K
SK
Sahoo
Centro de Desenvolvimento da Tecnologia Nuclear - CDTN, Belo Horizonte, MG, Brazil.
Carla O F
CO
Gonçalves
Centro de Desenvolvimento da Tecnologia Nuclear - CDTN, Belo Horizonte, MG, Brazil.
Adelina P
AP
Santos
Centro de Desenvolvimento da Tecnologia Nuclear - CDTN, Belo Horizonte, MG, Brazil.
Clascídia A
CA
Furtado
Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
Cristiano
C
Fantini
Laboratório de Neurociências / Programa de Pós Graduação em Ciências Fisiológicas - Fisiologia Animal Comparada, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande - FURG, Rio Grande, RS, 96210-900, Brazil.
Daniela M
DM
Barros
D000818:Animals; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D004625:Embryo, Nonmammalian / Q000187:drug effects* / Q000502:physiology; D047108:Embryonic Development / Q000187:drug effects* / Q000235:genetics; D006339:Heart Rate / Q000187:drug effects; D009043:Motor Activity / Q000187:drug effects; D009153:Mutagens / Q000633:toxicity*; D037742:Nanotubes, Carbon / Q000737:chemistry / Q000633:toxicity*; D011092:Polyethylene Glycols / Q000737:chemistry / Q000633:toxicity*; D013499:Surface Properties; D016019:Survival Analysis; D015027:Zebrafish / Q000196:embryology
D009153:Mutagens; D037742:Nanotubes, Carbon; D011092:Polyethylene Glycols
embryotoxicity; single-walled carbon nanotubes; zebrafish