Recent advances in localized surface plasmon resonance (LSPR) sensing technologies

Localized surface plasmon resonance (LSPR) is an optical phenomenon associated with noble metal nanostructures. The resonances result in sharp spectral absorption peaks as well as enhanced local electromagnetic fields, which have been widely used in chemical and biological sensing. Over the past decade, as label-free analytical method, LSPR sensors have gained considerable interest and undergone rapid development. In addition to conventional refractive-index sensing through resonant wavelength shift, molecular sensing by colorimetry and imaging techniques have also been developed. Moreover, the LSPR sensors have been integrated with other techniques such as micro/nano fluidics and artificial intelligence (AI) to enhance their functionality and performances. In this work, we provide an overview of the recent advancement in LSPR sensors technology, including refractive-index, colorimetric, and imaging-based sensors, as well as the incorporation of new technologies like AI.