• Advances in nano research
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• v.9 no.2
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• pp.113-122
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• 2020

Surface-Enhanced Raman Scattering (SERS) spectroscopy is a multifaceted surface sensitive methodology which exploits spectroscopy-based analysis for various applications. This technique is based on the massive amplification of Raman signals which were feeble previously in order to use them for appropriate identification at qualitative and quantitative in chemical as well as biological systems. This novel powerful technique can be utilized to identify pathogens such as bacteria and viruses. As far as SERS is concerned, one of the most studied problems has been functionalization of SERS active substrate. Metal colloids and nanostructures or microstructures synthesized using noble metals such as Au, Ag and Cu are considered to be SERS active. Silver and gold are extensively used as SERS active substrates due to chemical inertness and stability in air compare to copper. However, use of Cu as a suitable alternative has been taken into account as it is cheap. Herein, we have synthesized air-stable copper microstructures/nanostructures by chemical, electrochemical and microwave-assisted methods. In this paper, we have also discussed the use of as synthesized copper micro/nanostructures as inexpensive yet effective SERS active substrates for the fast identification of micro-organisms like Staphylococcus aureus and Escherichia coli.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.6
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• pp.459-464
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• 2008

We present a novel microcantilever device with nano-interdigitated electrodes (nano-IDEs) and DNA selective immobilization on the nano-IDEs for biosensing applications. Using the nano-IDEs and cyclic voltammetric methods, we have achieved selective immobilization of DNA with submicrometer spatial resolution on a freestanding microcantilever. $70{\sim}500\;nm$-wide gold (Au) nano-IDEs are fabricated on a low-stress SiNx microcantilever with dimensions of $100{\sim}600\;{\mu}m$ in length, and $15{\sim}60\;{\mu}m$ in width, with a $0.5\;{\mu}m$ thickness using electron beam lithography and bulk micromachining. Streptavidin is selectively deposited on one side of the nano-IDEs using cyclic voltammetry at a scan rate of 0.1 V/s with a range of $-0.2{\sim}0.7\;V$ during $1{\sim}5$ cycles. The selective deposition of dsDNA is confirmed by fluorescence microscopy after labeling with YOYO-1 dye.