Key Laboratory of MOE for Plant Development Biology, College of Life Sciences, Wuhan University, Wuhan 430072, China.
Plant Physiol Biochem. 2010 Aug;48(8):703-9. doi: 10.1016/j.plaphy.2010.04.001. Epub 2010 Apr 14.
Quantum dots (QDs) are a novel type of small, photostable and bright fluorophores that have been successfully applied to mammalian and human live cell imaging. In this study, highly dispersive water-soluble mercaptoacetic acid (MAA)-coated CdSe/ZnS QDs were synthesized, which were suitable for investigation as fluorescent probe labels. The treatment of maize seedling roots with QDs showed that the surfactant silwet L-77 aided the efficient transport of QDs into maize roots. Under a concentration ranging from 0.128 to 1.28 microM, QDs caused very low cytotoxicity on maize seed germination and root growth. The addition of mercuric chloride to the Hoagland solution resulted in a decrease of QD content in root tissues, and this decrease was reversed upon the addition of beta-mercaptoethanol, which suggests that mercury-sensitive processes play a significant role in regulating QD flow in the maize root system. We speculate that the apoplastic pathway can contribute substantially to the total quantity of QDs reaching the stele. Therefore, based on this transport approach, MAA-coated QDs can be utilized for live imaging in plant systems to verify known physiological processes.
量子点（QDs）是一种新型的、光稳定性强且明亮的荧光团，已成功应用于哺乳动物和人类活细胞成像。在这项研究中，我们合成了高度分散的水溶性巯基乙酸（MAA）包覆的 CdSe/ZnS QDs，适合作为荧光探针标记物进行研究。用 QDs 处理玉米幼苗根后，表明表面活性剂 Silwet L-77 有助于 QDs 高效地进入玉米根中。在 0.128 到 1.28 microM 的浓度范围内，QDs 对玉米种子萌发和根生长的细胞毒性非常低。在 Hoagland 溶液中加入氯化汞会导致根组织中 QD 含量减少，而加入β-巯基乙醇则会使 QD 含量恢复，这表明汞敏感过程在调节玉米根系中 QD 流动方面起着重要作用。我们推测质外体途径可以对到达中柱的 QD 总量做出重大贡献。因此，基于这种转运方法，MAA 包覆的 QDs 可以用于植物系统的活体成像，以验证已知的生理过程。
