Abstract

Surface plasmon resonance (SPR) has become an indispensable tool for label-free detection and quantification of molecular binding. Traditionally, the principle of SPR biosensors is described with a stratified medium model, in which discrete molecules are approximated with a uniform thin film. With the recent technical advances, SPR can now detect extremely low coverage of molecules, which raises the question of the validity of the traditional model. Here, we present combined theoretical, numerical and experimental analysis of SPR detection principle by considering the discrete nature of the molecules (particles). Our results show that the stratified medium model can provide reasonable description of SPR biosensors for relatively high coverage and weakly scattering samples. However, interference between the SPR images of individual particles needs to be considered for high spatial resolution images and for strong scattering samples at certain incident angles of light.

Original languageEnglish (US)
Pages (from-to)8992-8997
Number of pages6
JournalAnalytical chemistry
Volume86
Issue number18
DOIs
StatePublished - Sep 1 2014

ASJC Scopus subject areas

  • Analytical Chemistry

Fingerprint Dive into the research topics of 'Molecular scale origin of surface plasmon resonance biosensors'. Together they form a unique fingerprint.

  • Cite this