By a News Reporter-Staff News Editor at Life Science Weekly -- Researchers detail new data in Aromatic Amino Acids. According to news reporting originating in Melbourne, Australia, by NewsRx journalists, research stated, "The charge transfer-mediated surface enhanced Raman scattering (SERS) of crystal violet (CV) molecules that were chemically conjugated between partially polarized silver nanoparticles and optically smooth gold and silver substrates has been studied under off-resonant conditions. Tyrosine molecules were used as a reducing agent to convert silver ions into silver nanoparticles where oxidised tyrosine caps the silver nanoparticle surface with its semiquinone group."
The news reporters obtained a quote from the research from the Royal Melbourne Institute of Technology University, "This binding through the quinone group facilitates charge transfer and results in partially oxidised silver. This establishes a chemical link between the silver nanoparticles and the CV molecules, where the positively charged central carbon of CV molecules can bind to the terminal carboxylate anion of the oxidised tyrosine molecules. After drop casting Ag nanoparticles bound with CV molecules it was found that the free terminal amine groups tend to bind with the underlying substrates. Significantly, only those CV molecules that were chemically conjugated between the partially polarised silver nanoparticles and the underlying gold or silver substrates were found to show SERS under off-resonant conditions. The importance of partial charge transfer at the nanoparticle/capping agent interface and the resultant conjugation of CV molecules to off resonant SERS effects was confirmed by using gold nanoparticles prepared in a similar manner."
According to the news reporters, the research concluded: "In this case the capping agent binds to the nanoparticle through the amine group which does not facilitate charge transfer from the gold nanoparticle and under these conditions SERS enhancement in the sandwich configuration was not observed."
For more information on this research see: Probing the effect of charge transfer enhancement in off resonance mode SERS via conjugation of the probe dye between silver nanoparticles and metal substrates. Physical Chemistry Chemical Physics, 2013;15(31):12920-9. (Royal Society of Chemistry - www.rsc.org/; Physical Chemistry Chemical Physics - pubs.rsc.org/en/journals/journalissues/cp)
Our news correspondents report that additional information may be obtained by contacting P. Selvakannan, Center for Advanced Materials and Industrial Chemistry (CAMIC), School of Applied Sciences, RMIT University, Melbourne, VIC 3001, Australia. Additional authors for this research include R. Ramanathan, B.J. Plowman, Y.M. Sabri, H.K. Daima, A.P. O'Mullane, V. Bansal and S.K Bhargava (see also Aromatic Amino Acids).
Keywords for this news article include: Tyrosine, Melbourne, Nanoparticle, Nanotechnology, Aromatic Amino Acids, Emerging Technologies, Australia and New Zealand.
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