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Abstract The synthesis and reactivity of 3,8‐dibromo‐dodecafluoro‐benzo‐fused BOPHY2are reported, via SNAr with O‐, N‐ S‐ and C‐nucleophiles, and in Pd(0)‐catalyzed cross‐coupling reactions (Suzuki and Stille). The resulting perfluoro‐BOPHY derivatives were investigated for their reactivity in the presence of various nucleophiles. BOPHY3displays reversible color change and fluorescence quenching in the presence of bases (Et3N, DBU), whereas BOPHY7reacts preferentially at the α‐pyrrolic positions, and BOPHY8undergoes regioselective fluorine substitution in the presence of thiols. The structural and electronic features of the fluorinated BOPHYs were studied by TD‐DFT computations. In addition, their spectroscopic and cellular properties were investigated; BOPHY10shows the most red‐shifted absorption/emission (λmax659/699 nm) and7the highest fluorescence (Φf=0.95), while all compounds studied showed low cytotoxicity toward human HEp2 cells and were efficiently internalized.
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Detection of cancer‐associated miRNA using a fluorescence switch of AgNC@NA and guanine‐rich overhang sequences
Abstract DNA‐templated silver nanoclusters (AgNC@DNA) are a novel type of nanomaterial with advantageous optical properties. Only a few atoms in size, the fluorescence of nanoclusters can be tuned using DNA overhangs. In this study, we explored the properties of AgNCs manufactured on a short single‐stranded (dC)12when adjacent G‐rich sequences (dGN, withN = 3–15) were added. The ‘red’ emission of AgNC@dC12with λMAX = 660 nm dramatically changed upon the addition of a G‐rich overhang with NG = 15. The pattern of the emission–excitation matrix (EEM) suggested the emergence of two new emissive states at λMAX = 575 nm and λMAX = 710 nm. The appearance of these peaks provides an effective way to design biosensors capable of detecting specific nucleic acid sequences with low fluorescence backgrounds. We used this property to construct an NA‐based switch that brings AgNC and the G overhang near one another, turning ‘ON’ the new fluorescence peaks only when a specific miRNA sequence is present. Next, we tested this detection switch on miR‐371, which is overexpressed in prostate cancer. The results presented provide evidence that this novel fluorescent switch is both sensitive and specific with a limit of detection close to 22 picomoles of the target miR‐371 molecule.
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- Award ID(s):
- 2204027
- PAR ID:
- 10418783
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Luminescence
- Volume:
- 38
- Issue:
- 7
- ISSN:
- 1522-7235
- Page Range / eLocation ID:
- p. 1385-1392
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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