DNA-functionalized gold nanoparticle assemblies for Surface Enhanced Raman Scattering

Abstract

The programmable assembly of DNA strands is a promising tool for building tailored bottom-up nanostructures. Here, we present a plasmonic nanosystem obtained by the base-pairing mediated aggregation of gold nanoparticles (NPs) which are separately functionalized with two different single-stranded DNA chains. Their controlled assembly is mediated by a complementary DNA "bridge" sequence. We monitor the formation of DNA assembled NP aggregates in solution, and we study their Surface Enhanced Raman Scattering (SERS) response by comparison with the single NP constituents. We interpret the revealed SERS signatures in terms of the molecular and NP organization at the nanoscale, demonstrating that the action of the DNA bridge molecule yields regular NP aggregates with controlled interparticle distance and reproducible SERS response. This demonstrates the potential of the present system as a stable, biocompatible, and recyclable SERS sensor.

Unveiling the interaction of protein fibrils with gold nanoparticles by plasmon enhanced nano-spectroscopy

“…Similar to the TERS spectra, in the SERS spectrum, no Amide I band around 1650 cm -1 was detected. The intense band around 1600 cm -1 can be assigned to the asymmetric carboxylate stretching vibration of the citrate molecules forming the capping of the AuNPs [52][53][54] . This band is also detected in the control SERS spectrum reported in Fig.…”

A Comprehensive Review on Raman Spectroscopy Applications

“…Caprara et al [132] studied the DNA molecule formation using SERS with single DNA chain coated gold nanoparticles, comparing the Raman spectra of the final solution with the starting one. This paved the way for a bottom-up approach for the design of tailored nanostructures, taking advantage of the programmable assembly of DNA.…”

Recent Advances in Metallic Nanoparticle Assemblies for Surface-Enhanced Spectroscopy

“…A general strategy is centered upon DNA origami, in a process that involves the folding of DNA to create 2D and 3D objects at the nanoscale. In the simplest stable scenario, a biocompatible SERS-active system could be obtained by the covalently bonded functionalization of Au-NPs with specific DNA strands, as described by Caprara et al [ 121 ]. The mesoscopic aggregation of Au-NPs functionalized with 12-base single-stranded DNA sequences were induced by the addition of a complementary 24-base bridge sequence.…”