Well-designed metal nanostructured arrays for label-free plasmonic biosensing

Abstract

Localized surface plasmon resonance (LSPR) can concentrate light into nanometer-scale spatial regions, which increases the sensitivity to local refractive index changes in response to the presence of analytes on or near metal surfaces. LSPR-based nanostructured materials have great potential for being developed into large-scale arrays composed of highly miniaturized and uniform signal transducer elements, thus initiating high throughput screening platforms for refractometric biosensing. In this review, we present an overview of nanostructured materials with LSPRs and their applications in biosensing. First, we give a fundamental and practical introduction of the study of localized surface plasmon excitations in metal materials, and then focus on some well-designed nanostructures, in particular on thin perforated films and some quasi-three-dimensional structures. Each nanostructure is detailed and their plasmonic properties are briefly described. Subsequently, a brief summary of the fabrication methods for plasmonic nanostructures are presented. Finally, the future research trends of plasmonic biosensing are highlighted and a conclusion with perspectives is given.