Narrow bandgap Ag₂Te quantum dot (QDs) hold great promise in the fields of bioimaging, chemo-/bio-detection, and thermoelectric materials, but their biosafety has not been well estimated yet. In this study, we studied the biodistribution and toxicity of polyethylene glycol–coated Ag₂Te QDs (Ag₂Te QDs-PEG) in mice after a single intravenous injection. After entering the mice, Ag₂Te QDs-PEG displayed a short circulation time in the blood (half-life was less than 2 h), and mainly accumulated in the liver and spleen. The stability of Ag₂Te QDs-PEG in the mice depended on accumulation organ and time. Ag₂Te QDs-PEG were stable in the spleen within 28 days but decomposed in the liver after 7 days. The decomposed Ag₂Te QDs-PEG were eliminated from the body via different routes, as Ag was detected only in feces while Te was found only in urine. Meanwhile, Ag₂Te QDs-PEG did not show obvious adverse effects on the body weights, organ indices, biochemical parameters, the levels of essential metal Cu and Zn in organs, and organ pathological investigations during 28 days. In addition, the important effects of anion to the fates of silver chalcogenide QDs in vivo was demonstrated by comparing the distributions of the Ag₂Te QDs and other two silver chalcogenide QDs (Ag₂S and Ag₂Se). Our findings indicate Ag₂Te QDs have good biocompatibility in mice, which is a guarantee for their safe applications in the future.

窄带隙Ag ₂ Te量子点（QD）在生物成像，化学/生物检测和热电材料领域具有广阔的前景，但其生物安全性尚未得到很好的估计。在这项研究中，我们研究了单次静脉内注射后，涂有聚乙二醇的Ag ₂ Te QDs（Ag ₂ Te QDs-PEG）在小鼠中的生物分布和毒性。进入小鼠后，Ag ₂ Te QDs-PEG在血液中的循环时间短（半衰期少于2小时），并且主要在肝脏和脾脏中积累。Ag ₂ Te QDs-PEG在小鼠体内的稳定性取决于积累器官和时间。银₂Te QDs-PEG在28天内在脾脏中稳定，但在7天内在肝脏中分解。分解后的Ag ₂ Te QDs-PEG通过不同途径从体内清除，因为仅在粪便中检测到Ag，而仅在尿液中发现Te。同时，Ag ₂ Te QDs-PEG在28天内对体重，器官指标，生化参数，器官中必需金属Cu和Zn的含量以及器官病理学检查均未显示明显的不利影响。此外，通过比较Ag ₂ Te QD和其他两个硫属硫化物QD（Ag ₂ S和Ag ₂ Se）的分布，证明了阴离子对体内硫属硫化物QD命运的重要影响。我们的发现表明银₂ Te QD在小鼠中具有良好的生物相容性，这是其未来安全应用的保证。