Zhen Guo Wang1, Rong Zhou2, Dan Jiang1, Jing E Song1, Qian Xu1, Jing Si2, Yun Ping Chen1, Xin Zhou2, Lu Gan2, Jian Zhen Li3, Hong Zhang2, Bin Liu1. 1. School/Hospital of Stomatology, Lanzhou University, Lanzhou 730000, Gansu, China. 2. Department of Heavy Ion Irradiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, Gansu, China; Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, Gansu, China; Key Laboratory of Heavy Ion Radiation Medicine of Gansu Province, Lanzhou 730000, Gansu, China. 3. College of Life Sciences, Northwest Normal University, Lanzhou 730070, Gansu, China.
Abstract
OBJECTIVE: To evaluate the bio-safety of graphene quantum dots (GQDs), we studied its effects on the embryonic development of zebrafish. METHODS: In vivo, biodistribution and the developmental toxicity of GQDs were investigated in embryonic zebrafish at exposure concentrations ranging from 12.5-200 μg/mL for 4-96 h post-fertilization (hpf). The mortality, hatch rate, malformation, heart rate, GQDs uptake, spontaneous movement, and larval behavior were examined. RESULTS: The fluorescence of GQDs was mainly localized in the intestines and heart. As the exposure concentration increased, the hatch and heart rate decreased, accompanied by an increase in mortality. Exposure to a high level of GQDs (200 μg/mL) resulted in various embryonic malformations including pericardial edema, vitelline cyst, bent spine, and bent tail. The spontaneous movement significantly decreased after exposure to GQDs at concentrations of 50, 100, and 200 μg/mL. The larval behavior testing (visible light test) showed that the total swimming distance and speed decreased dose-dependently. Embryos exposed to 12.5 μg/mL showed hyperactivity while exposure to higher concentrations (25, 50, 100, and 200 μg/mL) caused remarkable hypoactivity in the light-dark test. CONCLUSION: Low concentrations of GQDs were relatively non-toxic. However, GQDs disrupt the progression of embryonic development at concentrations exceeding 50 μg/mL.
OBJECTIVE: To evaluate the bio-safety of graphene quantum dots (GQDs), we studied its effects on the embryonic development of zebrafish. METHODS: In vivo, biodistribution and the developmental toxicity of GQDs were investigated in embryonic zebrafish at exposure concentrations ranging from 12.5-200 μg/mL for 4-96 h post-fertilization (hpf). The mortality, hatch rate, malformation, heart rate, GQDs uptake, spontaneous movement, and larval behavior were examined. RESULTS: The fluorescence of GQDs was mainly localized in the intestines and heart. As the exposure concentration increased, the hatch and heart rate decreased, accompanied by an increase in mortality. Exposure to a high level of GQDs (200 μg/mL) resulted in various embryonic malformations including pericardial edema, vitelline cyst, bent spine, and bent tail. The spontaneous movement significantly decreased after exposure to GQDs at concentrations of 50, 100, and 200 μg/mL. The larval behavior testing (visible light test) showed that the total swimming distance and speed decreased dose-dependently. Embryos exposed to 12.5 μg/mL showed hyperactivity while exposure to higher concentrations (25, 50, 100, and 200 μg/mL) caused remarkable hypoactivity in the light-dark test. CONCLUSION: Low concentrations of GQDs were relatively non-toxic. However, GQDs disrupt the progression of embryonic development at concentrations exceeding 50 μg/mL.
Authors: Zaira Clemente; Gabriela Helena Silva; Miriam Celi de Souza Nunes; Diego Stéfani Teodoro Martinez; Claudia Vianna Maurer-Morelli; Andre Alexandre Thomaz; Vera Lúcia Scherholz Salgado Castro Journal: Environ Sci Pollut Res Int Date: 2019-08-28 Impact factor: 4.223
Authors: Bushra Khan; Adeyemi S Adeleye; Robert M Burgess; Roxanna Smolowitz; Stephen M Russo; Kay T Ho Journal: Environ Toxicol Chem Date: 2019-02-27 Impact factor: 3.742