ARTICLE
Tuning and Maximizing the Single-Molecule Surface-Enhanced Raman Scattering from DNA-Tethered Nanodumbbells Jung-Hoon Lee,† Jwa-Min Nam,*,† Ki-Seok Jeon,‡ Dong-Kwon Lim,† Hyoki Kim,§ Sunghoon Kwon,§ Haemi Lee,‡ and Yung Doug Suh*,‡ †
Department of Chemistry and §School of Electrical Engineering and Computer Science & Inter-University Semiconductor Research Center (ISRC), Seoul National University, Seoul 151-747, South Korea and ‡Laboratory for Advanced Molecular Probing (LAMP), NanoBio Fusion Research Center, Korea Research Institute of Chemical Technology, DaeJeon 305-600, South Korea
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eveloping and studying the surfaceenhanced Raman scattering (SERS)active nanostructures for highly sensitive molecular detection have been of great interest to many researchers since single-molecule SERS (SMSERS) was first reported in 1997.19 Typically, the SERS-active nanostructures contain the “hot-spot” regions, typically formed within the gap between plasmonic nanoparticles, and the distance and structural/chemical details between particles along with particle size, shape, and composition are known to play important roles in SERS.1017 This hot plasmonic junction can induce a strong electromagnetic field enhancement and also drastically amplify the Raman scattering signal by a factor of many orders of magnitude.16 However, the more complete and better understanding of this plasmonic coupling with respect to controlling the magnitude and distribution of the enhancement factors (EFs) based on the reliable data is limited due to the lack of the high-yield synthetic methods of the targeted plasmonic nanostructures with nanometer or subnanometer precision and high structural reproducibility. It is especially important to control a
