Label-Enhanced Surface Plasmon Resonance: A New Concept for Improved Performance in Optical Biosensor Analysis

Publication year: 2013
Authors: Niko Granqvist 1,2, Anders Hanning 3, Lars Eng 3, Jussi Tuppurainen 2, Tapani Viitala 1
Affiliations:

1 - Division of Biopharmaceutics and Pharmacokinetics, Faculty of Pharmacy, University of Helsinki, P.O Box 56, Helsingin Yliopisto 00014, Finland
2 - BioNavis Oy, Elopellontie 3C, Ylöjärvi 33470, Finland
3 - Episentec AB, Solna Strandväg 3, Solna 171 54, Sweden

Published in: Sensors, 2013, Vol. 13(11), p. 15348-15363
doi: 10.3390/s131115348

Surface plasmon resonance (SPR) is a well-established optical biosensor technology with many proven applications in the study of molecular interactions as well as in surface and material science. SPR is usually applied in the label-free mode which may be advantageous in cases where the presence of a label may potentially interfere with the studied interactions per se. However, the fundamental challenges of label-free SPR in terms of limited sensitivity and specificity are well known. Here we present a new concept called label-enhanced SPR, which is based on utilizing strongly absorbing dye molecules in combination with the evaluation of the full shape of the SPR curve, whereby the sensitivity as well as the specificity of SPR is significantly improved. The performance of the new label-enhanced SPR method was demonstrated by two simple model assays: a small molecule assay and a DNA hybridization assay. The small molecule assay was used to demonstrate the sensitivity enhancement of the method, and how competitive assays can be used for relative affinity determination. The DNA assay was used to demonstrate the selectivity of the assay, and the capabilities in eliminating noise from bulk liquid composition variations.


MP-SPR keywords: biosensor development, biotin-avidin interaction, competitive assay, dye, enhanced sensitivity, Label-Enhanced Surface Plasmon Resonance (SAMP-SPR), single-stranded DNA detection, small molecule detection