Teo Yin Nah, Wilson James N, Kool Eric T
Department of Chemistry, Stanford University, Stanford, California 94305, USA.
J Am Chem Soc. 2009 Mar 25;131(11):3923-33. doi: 10.1021/ja805502k.
We recently described the assembly of fluorescent deoxyriboside monomers ("fluorosides") into DNA-like phosphodiester oligomers (oligodeoxyfluorosides or ODFs) in which hydrocarbon and heterocyclic aromatic fluorophores interact both physically and electronically. Here we report the identification of a multicolor set of water-soluble ODF dyes that display emission colors across the visible spectrum, and all of which can be simultaneously excited by long-wavelength UV light at 340-380 nm. Multispectral dye candidates were chosen from a library of 4096 tetramer ODFs constructed on PEG-polystyrene beads using a simple long-pass filter to observe all visible colors at the same time. We resynthesized and characterized a set of 23 ODFs containing one to four individual chromophores and included 2-3 spacer monomers to increase aqueous solubility and minimize aggregation. Emission maxima of this set range from 376 to 633 nm, yielding apparent colors from violet to red, all of which can be visualized directly. The spectra of virtually all ODFs in this set varied considerably from the simple combination of monomer components, revealing extensive electronic interactions between the presumably stacked monomers. In addition, comparisons of anagrams in the set (isomers having the same components in a different sequence) reveal the importance of nearest-neighbor interactions in the emissive behavior. Preliminary experiments with human tumor (HeLa) cells, observing two ODFs by laser confocal microscopy, showed that they can penetrate the outer cellular membrane, yielding cytoplasmic localization. In addition, a set of four distinctly colored ODFs was incubated with live zebrafish embryos, showing tissue penetration, apparent biostability, and no apparent toxicity. The results suggest that ODF dyes may be broadly useful as labels in biological systems, allowing the simultaneous tracking of multiple species by color, and allowing visualization in moving systems where classical fluorophores fail.
我们最近描述了荧光脱氧核糖苷单体（“荧光苷”）组装成类DNA磷酸二酯寡聚物（寡脱氧荧光苷或ODFs）的过程，其中碳氢化合物和杂环芳香族荧光团在物理和电子方面相互作用。在此，我们报告了一组多色水溶性ODF染料的鉴定结果，这些染料在可见光谱范围内呈现发射颜色，并且所有染料都能被340 - 380 nm的长波长紫外光同时激发。多光谱染料候选物是从使用简单长通滤光片在聚乙二醇 - 聚苯乙烯珠上构建的4096个四聚体ODF库中挑选出来的，以便同时观察所有可见颜色。我们重新合成并表征了一组23种ODF，它们包含一到四个单独的发色团，并包含2 - 3个间隔单体以增加水溶性并使聚集最小化。该组的发射最大值范围为376至633 nm，产生从紫色到红色的表观颜色，所有这些都可以直接可视化。该组中几乎所有ODF的光谱与单体成分的简单组合有很大差异，这表明推测堆叠的单体之间存在广泛的电子相互作用。此外，该组中字谜异构体（具有相同成分但顺序不同的异构体）的比较揭示了最近邻相互作用在发射行为中的重要性。用人肿瘤（HeLa）细胞进行的初步实验，通过激光共聚焦显微镜观察两种ODF，结果表明它们可以穿透细胞膜外层，实现细胞质定位。此外，将一组四种颜色明显不同的ODF与活斑马鱼胚胎一起孵育，结果显示其具有组织穿透性、明显的生物稳定性且无明显毒性。结果表明，ODF染料在生物系统中作为标记物可能具有广泛的用途，能够通过颜色同时追踪多个物种，并能在传统荧光团无法发挥作用的动态系统中实现可视化。
