DNA detection using nanostructured SERS substrates with Rhodamine B as Raman label
DNA detection using nanostructured SERS substrates with Rhodamine B as Raman label
复制标题
DOI：
10.1016/j.bios.2008.03.032
复制
发表时间：
2008-10-15
影响因子：
12.6
通讯作者：
Kwong, Dim-Lee
中科院分区：
文献类型：
--
作者：
Fang, Cheng;Agarwal, Ajay;Kwong, Dim-Lee
展示了一种基于表面增强拉曼散射 (SERS) 的检测低浓度 DNA 杂交的技术，使用涂有金银的硅纳米结构作为基底。采用标准硅工艺技术来制造具有特征距离为 15 +/- 10 nm 的纳米间隙的 SERS 基底。目标 DNA 与半胱氨酸修饰的肽核酸 (PNA) 杂交，PNA 先前固定在纳米间隙中作为捕获位点。杂交后，从目标 DNA 主链引入的磷酸基团对无机接头 Zr4+ 表现出很强的亲和力。从而产生组装底物-PNA-DNA-Zr。由于 PNA 不具有磷酸基团，因此当互补 DNA 不发生杂交时，可以避免使用接头。随后，将底物-PNA-DNA-Zr 的组装体与拉曼标记罗丹明 B (RB) 一起孵育。 RB 中的羧酸基团与连接基 Zr4+ 发生反应，使该拉曼标签能够附着到组装底物 -PNA-DNA-Zr 上。选择RB对应的拉曼峰检测目标DNA，检测限为1 x 10(-12) M。(C) 2008 Elsevier B.V.保留所有权利。
A technique is demonstrated to detect DNA hybridization at low concentrations, based on Surface-Enhanced Raman Scattering (SERS) using silicon nanostructures coated with gold-silver as substrate. Standard silicon process technologies were employed to fabricate the SERS substrates featuring nanogaps with a characteristic distance of 15 +/- 10 nm. Target DNA was hybridized with cysteine-modified Peptide Nucleic Acids (PNA), which was previously fixed into the nanogaps as the capture sites. After hybridization, the introduced phosphate groups from the backbone of the target DNA showed strong affinity to an inorganic linker, Zr4+. so that resulting in the assembly substrate-PNA-DNA-Zr. Since PNA does not possess phosphate groups, the linker is avoided when there is no hybridization from the complimentary DNA. Subsequently, the assembly of substrate-PNA-DNA-Zr was incubated with a Raman label, Rhodamine B (RB). The carboxylic acid group in RB reacted with the linker Zr4+ allowing this Raman Label to be attached to the assembly substrate-PNA-DNA-Zr. The Raman peaks corresponding to RB were selected to detect the target DNA, with a detection limit of 1 x 10(-12) M. (C) 2008 Elsevier B.V. All rights reserved.