ja7b12772_si_001.pdf (1.38 MB)
Single-Molecule Analysis of MicroRNA and Logic Operations Using a Smart Plasmonic Nanobiosensor
Version 3 2018-03-22, 15:34
Version 2 2018-03-13, 14:19
Version 1 2018-03-09, 16:21
journal contribution
posted on 2018-03-21, 00:00 authored by Ying Zhang, Zhenhua Shuai, Hao Zhou, Zhimin Luo, Bing Liu, Yinan Zhang, Lei Zhang, Shufen Chen, Jie Chao, Lixing Weng, Quli Fan, Chunhai Fan, Wei Huang, Lianhui WangAnalysis
of biomolecules at the single-molecule level is a great
challenge in molecular diagnostics, gene profiling, and environmental
monitoring. In this work, we design a smart plasmonic nanobiosensor
based on individual Au@Ag core–shell nanocube (Au@Ag NC) modified
with tetrahedron-structured DNA (tsDNA) for detecting microRNA 21
(miR-21) at the single-molecule level. An average localized surface
plasmon resonance (LSPR) scattering spectral wavelength shift of approximately
0.4 nm can be obtained for a single miR-21 hybridization event on
the nanobiosensor. In addition, the sensing mechanism of the individual
Au@Ag NC is further verified by the three-dimensional finite-difference
time-domain (3D-FDTD) simulations. Notably, this system not only allows
the real-time detection of miR-21 with an aM level sensitivity over
a large dynamic range from 1 aM to 1 nM, but also enables DNA-based
logic operations as well as biomemory by exploiting miR-21, KpnI, and StuI-responsive assays. Our study
opens a unique method for single-molecule detection of biomolecules
and thus holds great promise in a variety of biological and biomedical
applications.