Localized surface plasmon resonance: a unique property of plasmonic nanoparticles for nucleic acid detection

Localized surface plasmon resonance (LSPR) of noble metal nanoparticles (a.k.a. plasmonic nanoparticles) opens up a new horizon for advanced biomolecule sensing. However, an effective and practical sensing system still requires meticulous design to achieve good sensitivity and distinctive selectivity for routine use and high-throughput detection. In particular, the detection of DNA and RNA is crucial in biomedical research and clinical diagnostics. This review describes the fundamental aspects of LSPR and provides an overall account of how it is exploited to assist in nucleic acid sensing. The detection efficiency of each LSPR-based approach is assessed with respect to the assay design, the selection of plasmonic nanoparticles, and the choice of nucleic acid probes which influence the duplex hybridization. Judicious comparison is made among various LSPR-based approaches in terms of the assaying time, the sensitivity or lowest sensing concentration (i.e. limit of detection or LOD), and the single-base mismatch (SBM) selectivity.