Enhancement of infrared absorption of low-temperature uracil thin films by a nanostructured silver surface
Publisher
AMER INST PHYSICSCitation
Enhancement of infrared absorption of low-temperature uracil thin films by a nanostructured silver surface 2016, 42 (2):106 Low Temperature PhysicsJournal
Low Temperature PhysicsRights
© 2016 AIP Publishing LLC.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
Enhancement of infrared absorption (SEIRA) of adsorbed biological molecules by a nanostructured metal surface is one of the main routes to increasing the sensitivity of modern optical biosensors. The FTIR absorption spectra of thin films of the RNA base uracil deposited on low-temperature substrate (T = 6K) with nanoscale silver structures were investigated in the spectral range 2700-600 cm(-1). It was shown that the intensity of the absorption bands corresponding to nu CO stretching vibrations (range 1800-1600 cm(-1)) of uracil (Ur) thin films increases 3-4 fold. For multi-layer films, the influence of the nanostructures on the vibrational spectra weakens, and for the film layers more than 15 nm away from the surface, the enhancement is essentially absent. The energies and the vibrational spectra of the complexes of uracil monomers and dimers with 20-atom tetrahedral silver nanoclusters were calculated by the quantum-mechanical method DFT/B3LYP. The most stable complexes have the coordination bond between the top of the silver tetrahedron and the oxygen of the carbonyl group C4O. It was found that the formation of such complexes significantly (3-5 fold) enhances the intensity of the nu C4O stretching vibration of uracil, while the intensities of the beta NH, beta CH and ring bending vibrations do not increase significantly. (C) 2016 AIP Publishing LLC.Note
12 month embargo; Published Online: February 2016ISSN
1063-777X1090-6517
Version
Final published versionSponsors
National Academy of Sciences of Ukraine [114U001070, 15/15H]; National Foundation for Basic Research of Ukraine [54.1/044]Additional Links
http://aip.scitation.org/doi/10.1063/1.4941965ae974a485f413a2113503eed53cd6c53
10.1063/1.4941965