State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China; University of Chinese Academy of Sciences, Beijing 100039, China.
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China; University of Chinese Academy of Sciences, Beijing 100039, China; Department of Chemistry and Physics, State University of New York at Stony Brook, New York, NY 11794-3400, USA.
Biosens Bioelectron. 2015 Dec 15;74:318-21. doi: 10.1016/j.bios.2015.06.044. Epub 2015 Jun 22.
In this paper, we developed a simple, low-cost and sensitive DNA sequences detection biosensor based on a label-free molecular beacon (MB) whose DNA hairpin structure terminal has a guanine-rich sequence that can enhance fluorescence of silver nanoclusters (Ag NCs). Without hybridization between hairpin probe and target DNA, the Ag NCs presented bright fluorescence for the proximity of guanine-rich sequences (GRSs). After binding with target DNA, the hairpin shape was destroyed which results in a decrease of the Ag NCs fluorescence intensity. With this biosensor, we detected three disease-related genes that were the human immunodeficiency virus (HIV) gene, hepatitis B virus (HBV) gene and human T-lymphotropic virus type I (HTLV-I) gene. The detection limits based on S/N of 3 were 4.4 nM, 6.8 nM and 8.5 nM for HIV gene, HBV gene and HTLV-I gene, respectively. Our sensor was also of high selectivity and could distinguish even one nucleotide mismatched target.
在本文中，我们开发了一种简单、低成本且灵敏的 DNA 序列检测生物传感器，该传感器基于无标记的分子信标（MB），其 DNA 发夹结构末端具有富含鸟嘌呤的序列，可增强银纳米簇（Ag NCs）的荧光。在发夹探针与目标 DNA 之间没有杂交的情况下，Ag NCs 由于靠近富含鸟嘌呤的序列（GRSs）而呈现明亮的荧光。与目标 DNA 结合后，发夹形状被破坏，导致 Ag NCs 荧光强度降低。利用该生物传感器，我们检测了三种与疾病相关的基因，即人类免疫缺陷病毒（HIV）基因、乙型肝炎病毒（HBV）基因和人类 T 淋巴细胞白血病病毒 I 型（HTLV-I）基因。基于信噪比为 3 的检测限分别为 HIV 基因、HBV 基因和 HTLV-I 基因的 4.4 nM、6.8 nM 和 8.5 nM。我们的传感器还具有很高的选择性，即使是一个核苷酸错配的靶标也能区分。
