Nanoplasmonics and Surface Enhanced Spectroscopy

SERS-based Biosensing on Plasmonic Silver Nanodomes

Mehmet KAHRAMAN1 Aysun KORKMAZ1, Handan YUKSEL2, Adile GURKAN1, Ramazan SOLMAZ2 

1 Department of Chemistry, Gaziantep University, 27310 Sehitkamil, Gaziantep, Turkey.
2 Department of Chemistry, Bingöl University, 12000 Bingöl, Turkey
E-mail: mskahraman46@gmail.com

Surface-enhanced Raman scattering (SERS) is an emerging analytical technique for the detection and identification of chemicals and biological molecules and structures. Rapid, sensitive and accurate identification of biomolecules and structures is critical not only clinical diagnostics but also industrial applications. Several studies have been demonstrated that SERS can be used as powerful technique for the identification of bacteria and proteins using different sample preparation methods and SERS substrates [1-3]. Sample preparation and SERS substrates are critical factors to obtain strong, sensitive, and reproducible SERS spectra from the analytes. In this study, label-free identification and characterization of bacteria and proteins on plasmonic silver nanodomes (AgNDs) structures is demonstrated. AgNDs are fabricated by combining of soft and nanosphere lithographies. First, convective-assembly method is used for the deposition of the latex particles (1600 nm) uniformly on a regular glass slide. After polydimethylsiloxane (PDMS) is poured on the latex thin film to obtain nanovoids on the PDMS surface.  The prepared nanovoids are used as template for AgNDs fabrication. Finally, the nanovoids are filled with silver (Ag) by electrochemical deposition to obtain AgNDs.  Different types of bacteria and proteins are used to test the performance of the fabricated AgNDs for SERS-based biosensing. 

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