Department of Chemistry, National Taiwan University, 1, Section 4, Roosevelt Road, Taipei 106, Taiwan.
Biosens Bioelectron. 2011 Jan 15;26(5):2431-5. doi: 10.1016/j.bios.2010.10.026. Epub 2010 Oct 21.
In this study, we prepared fluorescent, functional oligonucleotide-stabilized silver nanoclusters (FFDNA-Ag NCs) through one-pot synthesis and then employed them as probes for single nucleotide polymorphisms (SNPs). The FFDNA-Ag NCs were obtained through the NaBH(4)-mediated reduction of AgNO(3) in the presence of a DNA strand having the sequence 5'-C(12)-CCAGATACTCACCGG-3'. The specific DNA scaffold combines a fluorescent base motif (C(12)) and a specific sequence (CCAGATACTCACCGG) that recognizes a gene for fumarylacetoacetate hydrolase (FAH). The sensing mechanism of our new probe is based on the FFDNA-Ag NCs having different stabilities (fluorescence intensities) in solutions containing 150 mM NaCl in the absence and presence of perfect match DNA (DNA(pmt)). Under the optimal conditions (150 mM NaCl, 20 mM phosphate solution, pH 7.0), the fluorescence ratios of the FFDNA-Ag NC probes in the presence and absence of DNA(pmt), plotted against the concentration of DNA(pmt), was linear over the range 25-1000 nM (R(2)=0.98), with a limit of detection (S/N=3) of 14 nM. This cost-effective and simple FFDNA-Ag NC probe is sensitive and selective for SNPs of a gene for FAH.
在这项研究中，我们通过一锅合成法制备了荧光功能化的寡核苷酸稳定的银纳米簇（FFDNA-Ag NCs），并将其用作单核苷酸多态性（SNPs）的探针。FFDNA-Ag NCs 是通过在含有序列为 5'-C(12)-CCAGATACTCACCGG-3' 的 DNA 链的存在下，用 NaBH(4)介导的 AgNO(3)还原得到的。特定的 DNA 支架结合了荧光碱基基序（C(12)）和特定序列（CCAGATACTCACCGG），可识别延胡索酰乙酰乙酸水解酶（FAH）的基因。我们的新探针的传感机制基于 FFDNA-Ag NCs 在含有 150 mM NaCl 的溶液中和存在完美匹配 DNA（DNA(pmt)）时具有不同的稳定性（荧光强度）。在最佳条件下（150 mM NaCl，20 mM 磷酸盐溶液，pH 值 7.0），FFDNA-Ag NC 探针在存在和不存在 DNA(pmt)的情况下的荧光比值与 DNA(pmt)的浓度成线性关系，线性范围为 25-1000 nM（R(2)=0.98），检测限（S/N=3）为 14 nM。这种具有成本效益且简单的 FFDNA-Ag NC 探针对 FAH 基因的 SNPs 具有灵敏性和选择性。
