Preparation of Molecular Sentinel Based SERS Sensor for Hepatitis C Virus

Abstract

Construction of a rapid, cost-effective and label free biosensor is important issue for public health. In this study, it has been developed a sensitive, selective and simple biosensor for the detection of hepatitis C virus HCV DNA. For this purpose, firstly, superparamagnetic gold nanoparticles were prepared by simple citrate reduction method and used as surface enhanced Raman spectroscopy SERS substrate. Then, Raman labelled hairpin DNA molecular sentinel, MS was covalently bound on the gold shell by means of gold-sulfur interaction. After addition the complementary DNA target HCV DNA , the hairpin structure was changed closed state stem-loop configuration to open state hybridization configuration . As a result, the Raman label was located far away from the surface and reduced the SERS intensity. A good relationship was obtained between the decreasing of the SERS intensity and the target DNA concentration 0-50 pM and the limit of detection was found to be 0.1 pM. The sensing method only consists of a single hybridization and washing procedure after hybridization and centrifuge step can be omitted. It is believed that the prepared biosensor could be a powerful diagnostic tool for HCV detection.