Patterned Multiplex Pathogen DNA Detection by Au Particle-on-Wire SERS Sensor

Abstract

A Au particle-on-wire system that can be used as a specific, sensitive, and multiplex DNA sensor is developed. A pattern formed by multiple Au nanowire sensors provides positional address and identification for each sensor. By using this system, multiplex sensing of target DNAs was possible in a quantitative manner with a detection limit of 10 pM. Target DNAs from reference bacteria and clinical isolates were successfully identified by this sensor system, enabling diagnostics for infectious diseases.KEYWORDS DNA, multiplex, pathogen, pattern, surface-enhanced Raman scattering M ultiplex, sensitive, and specific DNA detection is of great demand for various biological and biomedical studies including gene profiling, drug screening, and clinical diagnostics because it has a potential to provide the most information from a small sample volume at low cost.1 In this regard, simple, reliable, and highthroughput methods that allow detection of multiple DNAs in one assay have been developed by taking various sensing approaches such as the measurement of fluorescence, [1][2][3] surface plasmon resonance (SPR), 4 electric signals, 5 and mass changes.6 Among these DNA sensing methods, fluorescence-based assay is currently the most preferred technique for multiplex DNA detection.7 Surface-enhanced Raman scattering (SERS) has also been considered as an attractive method for label-free multiplex DNA detection because of its single molecule level sensitivity, 8-10 molecular specificity, 11 and insensitivity to quenching. 7,12 These distinct advantages have led to the development of a number of ingenious SERS sensing platforms. [13][14][15][16] However, achieving optimum reproducibility of SERS signals and detecting various target molecules with a very small sample volume in one assay still remain as challenging tasks for practical multiplex SERS sensors. It has been shown that hot spots at nanoscale gaps between a nanowire (NW) and nanoparticles (NPs) can become highly SERS-active. [17][18][19][20][21][22] We have recently reported a new biomolecule detection method that provides reproducible SERS signals by using nanoscale gaps between Au NW and NPs. 23Here we present a multiplex DNA detection method employing multiple Au particle-on-wire systems as a SERS sensing platform. The system operates by the self-assembly of Au NPs onto Au NW in the presence of target DNAs, providing reproducible SERS signals in proportion to the concentrations of target DNAs. Multiple pathogen DNAs could be successfully detected by employing this method, demonstrating that this multiplex SERS sensor can be used a convenient system for clinical diagnostic and biomolecular interaction studies.Raman signal can be dramatically enhanced by placing the signal carrying molecules in the interstices between the assembled nanostructures. [24][25][26][27][28][29] To fabricate a SERS-active nanostructure that can be turned on by biomolecular binding, we adopted an Au particle-on-wire structure constructed by self-assembly of Au NPs onto Au NW through DN...

Au Nanowire‐on‐Film SERRS Sensor for Ultrasensitive Hg2+ Detection

“…Additionally, the development of portable and multiplex sensor would be feasible by using multiple kinds of aptamers and correspondingly modified NWs. [22] Experimental Section Materials: Purified DNAs were obtained from Genotech (Daejeon, Korea). The metal salts (Hg(Ac) 2 , Mg(Ac) 2 , Ca(Ac) 2 , CrCl 2 , FeCl 2 , Co(Ac) 2 , NiCl 2 , CuCl 2 , Zn(Ac) 2 , Cd(Ac) 2 , and Pb(Ac) 2 ) were purchased from Sigma-Aldrich.…”

Multiplex DNA Biosensor for Viral Infection Diagnosis Using SERS Molecular Sentinel-on-Chip

“…By profiling gene expression in peripheral blood in response to respiratory viral infection, a recent study showed that these two genes are among a set of host genes differentially expressed upon viral infection [27][28][29]. It is noteworthy that before our work, various SERSbased multiplex DNA detection techniques have been reported [30][31][32][33][34][35][36]. However, most of these techniques require multiple hybridization and/or washing steps or target sequences labeling.…”

Performance Improving Method of Aligned Silver Nanorod by Grafting Au@Ag Core–Shell Nanoparticles for Surface-Enhanced Raman Scattering

“…[1][2][3] Since it was discovered in the 1970s, SERS has been proven to be a sensitive technique for the detection of chemical and biological agents. [4][5][6][7][8] To widen the application of SERS technique, a great many of noble metal structures with complex morphologies [9][10][11][12][13] and controllable period [14][15][16] were investigated. The substrates based on these noble metal structures can be divided into nanoparticles (NPs) colloidal solution and solid-phase nanostructure.…”