Seo Daeha, Farlow Justin, Southard Kade, Jun Young-Wook, Gartner Zev J
Department of Otolaryngology, University of California, San Francisco; Department of Chemistry, University of California, Berkeley; Materials Science Division, Lawrence Berkeley National Laboratory.
Department of Pharmaceutical Chemistry, University of California, San Francisco; Tetrad Graduate Program, University of California, San Francisco; Center for Systems and Synthetic Biology, University of California, San Francisco.
J Vis Exp. 2014 Oct 23(92):e52198. doi: 10.3791/52198.
The multivalent nature of commercial quantum dots (QDs) and the difficulties associated with producing monovalent dots have limited their applications in biology, where clustering and the spatial organization of biomolecules is often the object of study. We describe here a protocol to produce monovalent quantum dots (mQDs) that can be accomplished in most biological research laboratories via a simple mixing of CdSe/ZnS core/shell QDs with phosphorothioate DNA (ptDNA) of defined length. After a single ptDNA strand has wrapped the QD, additional strands are excluded from the surface. Production of mQDs in this manner can be accomplished at small and large scale, with commercial reagents, and in minimal steps. These mQDs can be specifically directed to biological targets by hybridization to a complementary single stranded targeting DNA. We demonstrate the use of these mQDs as imaging probes by labeling SNAP-tagged Notch receptors on live mammalian cells, targeted by mQDs bearing a benzylguanine moiety.
商业量子点（QDs）的多价性质以及制备单价量子点的困难限制了它们在生物学中的应用，而生物分子的聚集和空间组织往往是生物学研究的对象。我们在此描述一种制备单价量子点（mQDs）的方法，大多数生物研究实验室都可以通过将CdSe/ZnS核壳量子点与特定长度的硫代磷酸酯DNA（ptDNA）简单混合来实现。单链ptDNA包裹量子点后，其他链就会被排除在表面之外。以这种方式制备mQDs可以小规模或大规模进行，使用商业试剂，且步骤最少。这些mQDs可以通过与互补的单链靶向DNA杂交而特异性地导向生物靶点。我们通过用带有苄基鸟嘌呤部分的mQDs标记活哺乳动物细胞上的SNAP标记的Notch受体，展示了这些mQDs作为成像探针的用途。
