羧基化单壁碳纳米管对斑马鱼胚胎发育和形态的影响

Effect of carboxylated single-walled carbon nanotubes on the development and morphology of zebrafish embryos

目的:评价水环境中羧基化单壁碳纳米管(c-SWNTs)对斑马鱼胚胎发育和形态的影响。方法:根据国家标准GB/T21807-2008,取受精后6 h(6 hpf)健康斑马鱼胚胎暴露于不同浓度(40 mg/L、80 mg/L、160 mg/L)的c-SWNTs水分散液中,观察和分析24 hpf和96 hpf胚胎的孵化率、畸形率和死亡率。以扫描电子显微镜(SEM)和透射电子显微镜(TEM)分别观测80 mg/Lc-SWNTs对24 hpf斑马鱼胚胎绒毛膜形态和胚胎超微结构的影响。结果:与空白对照组相比,除了40 mg/L浓度组胚胎在96 hpf的孵化率明显降低外(P<0.05),各暴露组胚胎在24 hpf和96 hpf的孵化率、畸形率和死亡率均无显著差异;SEM结果显示,c-SWNTs聚集在胚胎绒毛膜外表面,难以穿透绒毛膜;TEM结果显示,在胚胎内部超微结构中未观测到明显的cSWNTs。结论:水环境中的羧基化单壁碳纳米管主要聚集在胚胎绒毛膜外表面,会影响部分胚胎的孵化时间,但对斑马鱼的发育无明显影响。

Objective:To evaluate the effect of carboxylated single-walled carbon nanotubes(c-SWNTs)on the development and morphology of zebrafish embryos in the water environment.Methods:Healthy zebrafish embryos were exposed to c-SWNTs of different concentrations(40 mg/L,80 mg/L and 160 mg/L)in aqueous dispersions at 6 h post fertilization(6 hpf).And the hatching rate,malformation rate and mortality rate of the embryos at 24 hpf and 96 hpf were observed and analysed.The effect of 80 mg/L c-SWNTs on the morphology and embryonic ultrastructure of the zebrafish embryos at 24 hpf was observed by scanning electron microscope(SEM)and transmission electron microscope(TEM),respectively.Results:Compared with the blank control group,there was no significant difference in the hatching rate,malformation rate and mortality rate of the embryos among exposed groups at 24 and 96 hpf,except for the hatching rate of embryos with a significant decrease in the 40 mg/L group at 96 hpf(P<0.05).SEM results showed that c-SWNTs aggregated on the outer surface of the embryonic chorionic membrane and had difficulty penetrating the chorionic membrane.TEM results showed that no significant c-SWNTs were observed in the internal ultrastructure of the embryos.Conclusion:The carboxylated singlewalled carbon nanotubes in the water environment mainly aggregate on the outer surface of the embryonic chorion and will affect the hatching time of some embryos,but have no significant effect on the development of zebrafish.