Department of Biomedical Engineering, McGill University, 3775 Rue University, Montreal, QC, Canada.
Nanoscale. 2010 Jan;2(1):114-21. doi: 10.1039/b9nr00130a. Epub 2009 Sep 29.
CdSe/ZnS quantum dots (QDs) conjugated to biomolecules that can act as electron donors are said to be "photosensitized": that is, they are able to oxidize or reduce molecules whose redox potential lies inside their band edges, in particular molecular oxygen and water. This leads to the formation of reactive oxygen species (ROS) and phototoxicity. In this work, we quantify the generation of different forms of ROS from as-synthesized QDs in toluene; water-solubilized, unconjugated QDs; QDs conjugated to the neurotransmitter dopamine; and dopamine alone. Results of indirect fluorescent ROS assays, both in solution and inside cells, are compared with those of spin-trap electron paramagnetic resonance spectroscopy (EPR). The effect of these particles on the metabolism of mammalian cells is shown to be dependent upon light exposure and proportional to the amount of ROS generated.
CdSe/ZnS 量子点（QDs）与可以作为电子供体的生物分子结合，被称为“光敏化”：也就是说，它们能够氧化或还原那些氧化还原电位位于它们能带边缘内的分子，特别是分子氧和水。这导致活性氧物种（ROS）和光毒性的形成。在这项工作中，我们量化了在甲苯中合成的 QDs、水溶性、未结合的 QDs、与神经递质多巴胺结合的 QDs 和单独的多巴胺从合成的 QDs 中生成不同形式的 ROS 的情况。间接荧光 ROS 测定的结果，无论是在溶液中还是在细胞内，都与自旋捕获电子顺磁共振波谱（EPR）的结果进行了比较。这些颗粒对哺乳动物细胞代谢的影响取决于光暴露，并且与生成的 ROS 量成正比。
