Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-Minamimachi, Chuo-ku, Kobe 650-0047, Japan.
Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20 Minatojima-Minamimachi, Chuo-ku, Kobe 650-0047, Japan.
Molecules. 2018 Nov 6;23(11):2889. doi: 10.3390/molecules23112889.
Nucleic acid stability and structure, which are crucial to the properties of fluorescent DNA-templated silver nanoclusters (DNA-Ag NCs), significantly change in ionic liquids. In this work, our purpose was to study DNA-Ag NCs in a buffer containing the hydrated ionic liquid of choline dihydrogen phosphate (choline dhp) to improve fluorescence for application in DNA detection. Due to the stabilisation of an i-motif structure by the choline cation, a unique fluorescence emission-that was not seen in an aqueous buffer-was observed in choline dhp and remained stable for more than 30 days. A DNA-Ag NCs probe was designed to have greater fluorescence intensity in choline dhp in the presence of a target DNA. A turn-on sensing platform in choline dhp was built for the detection of the gene, which is related to familial breast and ovarian cancers. This platform showed better sensitivity and selectivity in distinguishing a target sequence from a mutant sequence in choline dhp than in the aqueous buffer. Our study provides new evidence regarding the effects of structure on properties of fluorescent DNA-Ag NCs and expands the applications of fluorescent DNA-Ag NCs in an ionic liquid because of improved sensitivity and selectivity.
核酸的稳定性和结构对于荧光 DNA 模板银纳米团簇（DNA-Ag NCs）的性质至关重要，而在离子液体中，其稳定性和结构会发生显著变化。在这项工作中，我们的目的是在含有磷酸胆碱水合离子液体的缓冲液中研究 DNA-Ag NCs，以提高其荧光性能，从而应用于 DNA 检测。由于胆碱阳离子稳定了 i-motif 结构，因此在磷酸胆碱中观察到了在水溶液缓冲液中未观察到的独特荧光发射，并且在超过 30 天的时间内保持稳定。设计了一种 DNA-Ag NCs 探针，使其在存在靶 DNA 时在磷酸胆碱中具有更高的荧光强度。在磷酸胆碱中构建了一种用于检测与家族性乳腺癌和卵巢癌相关的基因的开环感测平台。与在水溶液缓冲液中相比，该平台在区分磷酸胆碱中的靶序列和突变序列方面表现出更好的灵敏度和选择性。我们的研究提供了关于结构对荧光 DNA-Ag NCs 性质影响的新证据，并由于提高了灵敏度和选择性，扩展了荧光 DNA-Ag NCs 在离子液体中的应用。
