Excitation of localized surface plasmon resonance using a core–shell structurednanoparticle layer substrate and its application for label-free detection of biomolecularinteractions

Abstract

The novel characteristics of nanomaterials enable highly sensitive and specific applicationsin electronics, optics and biotechnology. In particular, nanomaterials have become thepreferable tools for monitoring biomolecular interactions on a biochip withoutlabelling procedures using enzymes and fluorescent dyes. In this report, label-freedetection of hybridization between nucleic acids using localized surface plasmonresonance (LSPR) based on a core–shell structured nanoparticle layer substrate isdescribed. The core–shell structured nanoparticle layer substrate could be excitedusing LSPR phenomena, and its LSPR characteristics were controlled by applyingdifferent fabrication conditions. Using our LSPR label-free biochip, the opticalcharacteristics were monitored for the detection of specific DNA–DNA and PNA–DNAhybridization reactions. Furthermore, the detection limit of the LSPR label-free biochipwas 1 pM. The highly sensitive label-free detection of DNA hybridization waspossible in a short analysis time. As a result, the LSPR label-free biochip provides apromising platform with attractive advantages for the detection of biomolecularinteractions at low cost in a simplified experimental set-up with a low samplevolume.