• Bulletin of the Korean Chemical Society
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• v.9 no.4
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• pp.218-223
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• 1988

The surface-enhanced Raman scattering of L-phenylalanyl-glycine (L-Phe-Gly), L-phenylalanyl-glycyl-glycine (L-Phe-Gly-Gly), glycyl-glycyl-L-phenylalanine (Gly-Gly-L-Phe), L-tyrosyl-glycine (L-Tyr-Gly), and L-tyrosyl-glycyl-glycine (L-Tyr-Gly-Gly) adsorbed on silver colloidal particles have been investigated. More detailed investigations on the surface-enhanced Raman scattering from L-phenylalanine (L-Phe), glycyl-L-phenylalanine (Gly-L-Phe), L-tyrosine (L-Tyr), and glycyl-L-tyrosine (Gly-L-Tyr) than in ref. 17 have also been made. It has been found that the above molecules adsorb on the surface via both the carboxylate ($COO^-$) and amino ($NH_2$) groups.

• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.999-1003
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• 2010

Raman spectra of a single layer graphene sheet placed in different gold substrates were obtained and are discussed in the context of surface enhanced Raman scattering (SERS). The gold substrates were composed of a combination of a thermally deposited gold film and a close-packed gold nanosphere layer. The SERS effects were negligible when the excitation wavelength was 514 nm, while the Raman signals were enhanced 3-to 50-fold when the excitation wavelength was 633 nm. The large SERS enhancement accompanied a spectral distortion with appearance of several unidentifiable peaks, as well as enhancement of a broadened D peak. These phenomena are interpreted as the local field enhancement in the nanostructure of the gold substrates. The difference in the enhancement factors among the various gold substrates is explained with a model in which the spatial distribution and polarization of the local field and the orientation of the inserted graphene sheet are considered important.

• Analytical Science and Technology
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• v.8 no.3
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• pp.313-319
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• 1995

Surface-enhanced Raman scattering(SERS) spectroscopy was employed to analyze the genotoxic nucleobase adducts of benzo[a]pyrene(BP) formed through one-electron oxidation pathway. SERS spectroscopy provided sufficient resolution to distinguish if BP intermediate was bound to different nucleobases(e. g. adenine or guanine). Furthermore, SERS specroscopy was also able to detect the difference in the binding position of the adduct to the various sites of the nucleobase. The linearity of the calibration curve for N7Ade-BP ranged from 20 picogram to 800 nanogram per microliter and the detection limit under the current conditions was determined 20 picogram per microliter in a solution volume of 20 microliter.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.470-474
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• 2013

Surfaced-enhanced Raman scattering (SERS) of 4,4'-biphenyldithiol (BPDT) has been investigated at a silver island film. Ordinary Raman (OR) spectra of neat sample in solid state and in basic solution have also been taken for comparison. The spectral feature in the SERS spectrum was similar to that for the OR spectrum in basic solution, except for the broadening of ring stretching bands indicative of the presence of surface-phenyl ring $\pi$ interaction. In contrast, only absence of the C-H stretching band with very small Raman scattering cross-section seemed not pertinent in judging the definitive orientation of molecule. The observed vibrational bands in the SERS spectrum have been assigned by referring to the normal modes and wavenumbers from density functional theory (DFT) calculations of the simple model as 4,4'-biphenyldithiolates bound to two Ag atoms at the both ends. Excellent agreement between the experimental and the calculated results was achieved, which is remarkable considering the level of theory applied.

• The Plant Pathology Journal
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• v.29 no.1
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• pp.105-109
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• 2013

Raman spectroscopy provides many advantages compared to other common analytical techniques due to its ability of rapid and accurate identification of unknown specimens as well as simple sample preparation. Here, we described potential of Raman spectroscopic technique as an efficient and high throughput method to detect plants infected by economically important viruses. To enhance the detection sensitivity of Raman measurement, surface enhanced Raman scattering (SERS) was employed. Spectra of extracts from healthy and Turnip yellow mosaic virus (TYMV) infected Chinese cabbage leaves were collected by mixing with gold (Au) nanoparticles. Our result showed that TYMV infected plants could be discriminated from non-infected healthy plants, suggesting the current method described here would be an alternative potential tool to screen virus-infection of plants in fields although it needs more studies to generalize the technique.

• Korean Journal of Optics and Photonics
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• v.1 no.2
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• pp.142-148
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• 1990

Surface-enhanced Raman scattering (SERS) experiment of pyridine (CsHsN) has been performed at silverpyridine interface by use of long range surface plasmon (LRSP) which is generated in the Sarid-type attenuated total reflection (A TR) structure consisting of prism. dielectric. metal and dielectric media. Generation of LRSP has ben confirmed by observing the propagation of the LRSP. Raman signal of pyridine adsorbed on a silver surface in the above layered structure has been observed and compared with the bulk Raman signal and SERS signal from the chemically adsorbed pyridine. SERS experiment by use of LRSP has not yet reported to the best of our knowledge.wledge.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1215-1218
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• 2010

We demonstrate the possible application of the sandwich type surface-enhanced Raman scattering (SERS) immunoassay using antigen-antibody binding for detection of prostate-specific antigen (PSA) in cancer cells. In this sandwich type of SERS immunoassay, to capture antigens onto the immobilized layer of antibodies on the gold substrate we prepared the monolayer of gold nanoparticles on the APTMS-derivatized surface of a glass slide by using the SAM technique. This sandwich type of SERS immunoassay in which antigens on the substrate specifically capture antibodies on a Raman reporter (DSNB coated gold nanoparticles with R6G) could successfully detect PSA at low levels. A strong SERS spectrum of Raman reporter was observed only with a substrate in which PSA is present.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2930-2934
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• 2009

Surface-enhanced Raman Scattering (SERS) spectroscopy is applied to the study of the adsorption of benzoimidazolic fungicides benzimidazole (BIZ) and thiabendazole (TBZ) on silver mirrors. The influence of pH on the adsorption mechanism was investigated. In case of BIZ, two different adsorption mechanisms are deduced depending on the experimental conditions: via the $\pi$ electrons of the ring in neutral conditions and through an ionic pairing of protonated nitrogen atom with the chloride adsorbed on the metal surface. The SERS spectra of TBZ revealed that most molecules were adsorbed on silver surface by the ${\pi}$ electrons in neutral and acidic conditions but in acid conditions, some molecules were adsorbed via the sulfur and nitrogen atoms tilted slightly to the surface.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.237-242
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• 2013

This experiment was conducted for the purpose of developing such a sensor that can quickly sense dopamine concentration by using chitosan-gold nanoshell. Chitosan nano particles were reacted with gold nano particles so as to synthesize chitosan-gold nanoshell, and the size of the synthesized product was about 150 nm. When dopamine was reacted with chitosan-gold nanoshell, the size of it was not definitely changed, but dopamine was well reacted with chitosan-gold nanoshell, and it generated SERS (surface-enhanced Raman scattering), which led to a clear difference in the intensity of Raman scattering within the range of dopamine concentration (1 mM-10 mM). When Raman scattering was intensity marked on chitosan-gold nanoshell by employing a calibration curve according to dopamine concentration, a straight line whose margin of error was narrow was earned.

• Analytical Science and Technology
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• v.8 no.4
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• pp.699-705
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• 1995

Monolayers of hypericin, a photodynamic polycyclic quinoidal compound, were prepared at the air-water interface, and were transferred to metal substrates to form Langmuir-Blodgett (LB) monolayers. The structural characteristics of hypericin LB monolayers and self-assembled (SA) monolayers were investigated using surface-enhanced resonance Raman scattering (SERRS) spectroscopy. Both the spectroscopic data and the surface pressure - area (${\pi}-A$) isotherms suggest that hypericin forms ${\pi}-{\pi}$ aggregates that orient vertically to the subphase surface. Whereas the ordering and orientation of control was less effective in SA monolayers, a higher structural regularity was attained in LB systems. The effect of subphase on the structural integrity of the monolayer was also investigated.