In this study, the effects of doping of CQDs with alternative functional groups (dopants) were evaluated through embryonic development of zebrafish (Danio rerio). The CQDs were synthesized using simple and low-cost sources: Non-doped (citric acid was used as the carbon source), nitrogen-doped (N-doped) and nitrogen, sulfur-co-doped (N,S-doped). The CQDs induced significant toxicity to zebrafish (>150 μg/mL) and the toxic effects were dose-dependent. The N,S-doped CQDs were the most toxic (LD50 = 149.92 μg/mL), followed by the N-doped CQDs (LD50 = 399.95 μg/mL) while the non-doped CQDs were the least toxic (LD50 = 548.48 μg/mL) of the three. The growth rate (GR) was affected following the toxicity pattern (GR_NS-doped<GR_N-doped<GR_non-doped <GR_blanc), which, in turn, greatly depends on the type of dopant. Morphological malformations, such as pericardial edema, yolk sac edema, tail and spinal curvature were observed to zebrafish embryos as the toxicity, concentration and exposure time to the nanomaterial increased. Behavioral analysis showed that locomotor activity increases as the toxicity of the nanomaterial rises. The differences in toxicity, growth rate and malfunctions of CQDs were attributed to their doping with different heteroatoms. The N,S-doped CQDs, unequivocally, exhibited the most pronounced effects.

在这项研究中，通过斑马鱼（Danio rerio）的胚胎发育评估了使用其他官能团（掺杂剂）掺杂CQD的效果。使用简单且低成本的来源合成了CQD：未掺杂（柠檬酸用作碳源），氮掺杂（N掺杂）和氮硫共掺杂（N，S掺杂）。CQD对斑马鱼具有明显的毒性（> 150μg/ mL），且毒性作用与剂量有关。N，S掺杂的CQD毒性最高（LD50 = 149.92μg/ mL），其次是N掺杂的CQDs（LD50 = 399.95μg/ mL），而非掺杂的CQD毒性最低（LD50 = 548.48μg / mL）的三个。生长速率（GR）受到毒性模式的影响（GR _NS掺杂<GR _N掺杂<GR_非掺杂<GR _blanc），这在很大程度上取决于掺杂剂的类型。随着纳米材料的毒性，浓度和暴露时间的增加，观察到斑马鱼胚胎的形态畸形，例如心包水肿，卵黄囊水肿，尾巴和脊柱弯曲。行为分析表明，运动活性随纳米材料毒性的增加而增加。CQDs毒性，生长速率和功能障碍的差异归因于它们掺杂了不同的杂原子。毫无疑问，N，S掺杂的CQD表现出最明显的效果。