Development of Aptamer-Based Sensor for Quantitative Detection of Mercury (II) Ions by Surface-Enhanced Infrared Absorption Spectroscopy

Abstract

In this study a quantitative mercuric ion detection system was developed with aptamer and infrared absorption spectroscopy Nano-crystalline island-shaped gold film was deposited on polycrystalline silicon prism by electroless plating process to amplify signal of incident light and effectively lower the limit of detection Aptamers have been widely used in a variety of fields including drug development in the last two decades microbiological sensing and environmental monitoring through proper sequence design Compared with the cost and restrictions while using or preserving of monoclonal antibody aptamer has many advantages such as mass production by PCR low cost and high stability The attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) was used to investigate due to high sensitivity high resolution of time surface selectivity and low solution background interference In this research 32-mer of single-stranded DNA sequence was used as the specific aptamer to capture mercuric ions Methylene blue (MB) was linked at 3’ end of aptamer as optical indicator and mercaptohexane (MCH) was immobilized at the opposite end as a linker with gold The configuration of aptamer will transform into hairpin shape after combining with Hg(II) so that methylene blue will move from bulk to surface With this feature the optimal parameters of surface aptamer modification and corresponding linear detection range / limit of detection were further confirmed

Date of Award	2017 Aug 24
Original language	English
Supervisor	Ruey-Jen Yang (Supervisor)