Silver nanomaterials for the detection of chemical and biological targets

Silver nanomaterials have attracted a lot of interest from researchers, mainly owing to their distinctive optical properties such as localized surface plasmon resonance (LSPR) and surface-enhanced Raman scattering (SERS). These properties are particularly interesting for the diagnostic applications when combined with target-recognition capabilities of surface ligands and target concentration-dependent quantitative aspects of the LSPR or SERS signal. This review covers these two main optical properties of silver nanomaterials with respect to their sensing applications for various chemical and biological targets. The LSPR-based colorimetric detection schemes are further divided into two categories based on what they depend on: (1) assembly and (2) deformation of the silver nanoparticle probes. Because the various shapes of the silver nanomaterials are highly associated with how to design and control the LSPR- and SERS-based detection schemes, the latest progress in the development of highly sensitive and selective detection strategies are discussed with respect to the morphological diversity of the silver nanomaterials.