Institute of Physiology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, Berlin 10117, Germany.
Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa.
Int J Pharm. 2014 May 15;466(1-2):382-9. doi: 10.1016/j.ijpharm.2014.03.037. Epub 2014 Mar 20.
Semiconductor quantum dots (QDs) have become promising nanoparticles for a wide variety of biomedical applications. However, the major drawback of QDs is their potential toxicity. Here, we determined possible cytotoxic effects of a set of QDs by systematic photophysical evaluation in vitro as well as in vivo. QDs were synthesized by the hydrothermal aqueous route with sizes in the range of 2.0-3.5 nm. Cytotoxic effects of QDs were studied in the human pancreatic carcinoid cell line BON. Cadmium telluride QDs with or without zinc sulfide shell and coated with 3-mercaptopropionic acid (MPA) were highly cytotoxic even at nanomolar concentrations. Capping with l-glutathione (GSH) or thioglycolic acid (TGA) reduced the cytotoxicity of cadmium telluride QDs and cadmium selenide QDs. Determination of the toxicity of QDs revealed IC50 values in the micromolar range. In vivo studies showed good tolerability of CdSe QDs with ZnS shell and GSH capping. We could demonstrate that QDs with ZnS shell and GSH capping exhibit low toxicity and good tolerability in cell models and living organisms. These QDs appear to be promising candidates for biomedical applications such as drug delivery for enhanced chemotherapy or targeted delivery of light sensitive substances for photodynamic therapy.
半导体量子点（QDs）已成为广泛应用于生物医学领域的一种很有前途的纳米粒子。然而，QDs 的主要缺点是其潜在的毒性。在这里，我们通过体外和体内的系统光物理评估来确定一组 QDs 的可能细胞毒性作用。通过水热法在水溶液中合成了尺寸在 2.0-3.5nm 范围内的 QDs。在人胰腺类癌细胞系 BON 中研究了 QDs 的细胞毒性作用。带有或不带有硫化锌壳并涂有 3-巯基丙酸（MPA）的碲化镉 QDs 在纳摩尔浓度下就具有很高的细胞毒性。用 L-谷胱甘肽（GSH）或硫代乙醇酸（TGA）封端可降低碲化镉 QDs 和硒化镉 QDs 的细胞毒性。确定 QDs 的毒性揭示了在微摩尔范围内的 IC50 值。体内研究表明，带有 ZnS 壳和 GSH 封端的 CdSe QDs 具有良好的耐受性。我们可以证明，带有 ZnS 壳和 GSH 封端的 QDs 在细胞模型和生物体中表现出低毒性和良好的耐受性。这些 QDs 似乎是用于药物输送以增强化学疗法或用于光动力疗法的光敏物质的靶向递药等生物医学应用的有前途的候选物。
