Quantum dots (QDs), as one of the emerging nanomaterials, have been widely studied by scientists due to their advantages and potential in bioimaging, especially cell imaging. Cadmium (Cd)‐based QDs, which have the best photoluminescence property, have received widespread attention. However, due to the obvious toxicity problem of these QDs, their cell imaging application is hindered. Recently, the emergence of Cd‐free‐metal and metal‐free QDs with lower toxicity makes people consider that Cd‐based QDs may be substituted by these QDs. However, problems of these QDs in cytotoxicity also cannot be ignored. Some reports claimed that their prepared emerging QDs for cell imaging were low toxicity, but there still exist up‐regulation of oxidative stress, inflammation, and apoptosis from other reports. And, up to now, few reports have separately summarized and discussed the issues of cell imaging and cytotoxicity of different types of QDs. Therefore, in this review, we classify QDs as following three types, Cd‐based, Cd‐free‐metal and metal‐free QDs, focus on the cell, the essential unit of life, discuss cell imaging application and cytotoxicity of QDs, and finally elucidate main mechanisms of cytotoxicity respectively. This review provides reference for the toxicity evaluation of QDs and highlights the potential cytotoxicity of Cd‐free QDs.

中文翻译：

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不同类型量子点的细胞成像及细胞毒性研究进展

量子点（QDs）作为新兴的纳米材料之一，由于其在生物成像，尤其是细胞成像方面的优势和潜力，被科学家们广泛研究。镉（Cd）基量子点具有最佳的光致发光性能，受到了广泛的关注。然而，由于这些量子点明显的毒性问题，阻碍了它们的细胞成像应用。最近，毒性较低的无镉金属和无金属量子点的出现，使人们认为基于镉的量子点可能被这些量子点所取代。然而，这些量子点在细胞毒性方面的问题也不容忽视。一些报道声称他们制备的用于细胞成像的新兴量子点毒性低，但其他报道仍存在氧化应激、炎症和细胞凋亡的上调。而且，到目前为止，很少有报道单独总结和讨论不同类型量子点的细胞成像和细胞毒性问题。因此，在这篇综述中，我们将 QDs 分为以下三种类型，Cd-based、Cd-free-metal 和 metal-free QDs，关注细胞，生命的基本单位，讨论 QDs 的细胞成像应用和细胞毒性，以及最后分别阐明细胞毒性的主要机制。该综述为量子点的毒性评估提供了参考，并强调了无镉量子点的潜在细胞毒性。最后分别阐明细胞毒性的主要机制。该综述为量子点的毒性评估提供了参考，并强调了无镉量子点的潜在细胞毒性。最后分别阐明细胞毒性的主要机制。该综述为量子点的毒性评估提供了参考，并强调了无镉量子点的潜在细胞毒性。