School of Environmental Science and Engineering, Shandong University, China -America CRC for Environment & Health, Shandong Province, 72# Jimo Binhai Road, Qingdao, Shandong, 266237, China.
College of Life Sciences, Hebei University, Baoding, 071000, China.
Ecotoxicol Environ Saf. 2020 Jun 15;196:110569. doi: 10.1016/j.ecoenv.2020.110569. Epub 2020 Apr 8.
Cadmium-quantum dots (Cd-QDs) possess unique properties as optoelectronic devices for sensitive detection in food and biomedicine fields. However, the toxic effects of Cd-QDs to single cells is still controversial, due to the release mechanism of QDs to Cdin situ and the cytotoxic effects of QDs and Cd respectively are still unclear. In this paper, the release rule of Cd from CdTe QDs within single cells was investigated in situ by using flow cytometry method and the dose-response relationships were explored. Besides, an all-inclusive microscopy system was optimized for live cell imaging to observe the real-time entry process of CdTe QDs into cells. We found that intracellular CdTe QDs and Cd contents were increased based on the dosage and exposing time. A dissociated saturation of Cd from CdTe QDs was exist within cells. CdTe QDs induced more serious cytotoxicity on kidney cells than hepatocytes. The toxicity of oxidative stress, cell apoptosis effects induced by CdTe QDs and Cd are also in consistent with this result. This research develops analytical method to quantify the uptake and release of Cd-QDs to primary cells in situ and can provide technical support in studying the cytotoxicity portion contributed by nanoparticles (NPs) and metal ions.
镉量子点（Cd-QDs）作为光电设备在食品和生物医学领域具有灵敏检测的独特性能。然而，由于 QDs 原位释放 Cd 的机制以及 QDs 和 Cd 各自的细胞毒性作用尚不清楚，因此 Cd-QDs 对单细胞的毒性作用仍存在争议。在本文中，我们使用流式细胞术原位研究了 CdTe QDs 中 Cd 的释放规律，并探讨了剂量-反应关系。此外，我们还优化了一个综合显微镜系统用于活细胞成像，以观察 CdTe QDs 进入细胞的实时过程。我们发现，基于剂量和暴露时间，细胞内的 CdTe QDs 和 Cd 含量增加。细胞内 CdTe QDs 中 Cd 的释放存在解离饱和。CdTe QDs 对肾小管细胞的细胞毒性比肝细胞更严重。CdTe QDs 和 Cd 诱导的氧化应激毒性、细胞凋亡效应也与这一结果一致。本研究开发了一种分析方法，可定量原位测定原代细胞对 Cd-QDs 的摄取和释放，可为研究纳米颗粒（NPs）和金属离子引起的细胞毒性部分提供技术支持。
