Label-free biosensing arrays based on phase-sensitive surface plasmon resonance imaging

The surface plasmon resonance (SPR) biosensor is a very powerful tool for studying binding mechanisms between all kinds of biomolecular species without the need of any tagging or labeling. However, application of SPR at present is largely confined to the laboratory environment and SPR biosensors are yet to be widely accepted by the point-of-care diagnostics industry. Despite its attractive label-free and real time measurement capabilities, the lack of sensitivity as compared to conventional fluorescence based techniques has been the main barrier. It has largely accepted that when the sensitivity issue is resolved, enormous commercialisation opportunities will follow as label-free detection techniques are just too attractive for the end-user who wants to quickly get to the identification of those target biomolecules.