International Joint Research Laboratory for Biointerface and Biodetection State Key Lab of Food Science and Technology School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu, 214122, P. R. China.
Small. 2020 Jun;16(23):e2000003. doi: 10.1002/smll.202000003. Epub 2020 May 6.
It is a significant challenge to achieve controllable self-assembly of superstructures for biological applications in living cells. Here, a two-layer core-satellite assembly is driven by a Y-DNA, which is designed with three nucleotide chains that hybridized through complementary sequences. The two-layer core-satellite nanostructure (C S S NS) is constructed using 30 nm gold nanoparticles (Au NPs) as the core, 5 nm Au NPs as the first satellite layer, and 10 nm Au NPs as the second satellite layer, resulting in a very strong circular dichroism (CD) and surface-enhanced Raman scattering. After optimization, the yield is up to 85%, and produces a g-factor of 0.16 × 10 . The hybridization of the target microRNA (miRNA) with the molecular probe causes a significant drop in the CD and Raman signals, and this phenomenon is used to detect the miRNA in living cells. The CD signal has a good linear range of 0.011-20.94 amol ng and a limit of detection (LOD) of 0.0051 amol ng , while Raman signal with the range of 0.052-34.98 amol ng and an LOD of 2.81 × 10 amol ng . This innovative dual-signal method can be used to quantify biomolecules in living cells, opening the way for ultrasensitive, highly accurate, and reliable diagnoses of clinical diseases.
在活细胞中实现用于生物应用的超结构可控自组装是一项重大挑战。在这里，通过设计具有通过互补序列杂交的三个核苷酸链的 Y-DNA 驱动双层核-卫星组装。双层核-卫星纳米结构（CSSNS）使用 30nm 金纳米粒子（AuNPs）作为核，5nmAuNPs 作为第一层卫星，10nmAuNPs 作为第二层卫星构建，从而产生非常强的圆二色性（CD）和表面增强拉曼散射。经过优化，产率高达 85%，并产生 0.16×10 的 g 因子。目标 microRNA（miRNA）与分子探针的杂交导致 CD 和拉曼信号显著下降，并且该现象用于检测活细胞中的 miRNA。CD 信号具有 0.011-20.94amolng 的良好线性范围和 0.0051amolng 的检测限（LOD），而拉曼信号的范围为 0.052-34.98amolng 和 2.81×10 的 LODamolng。这种创新的双信号方法可用于定量活细胞中的生物分子，为临床疾病的超灵敏、高精度和可靠诊断开辟了道路。
