Chiral Plasmonics and Their Potential for Point-of-Care Biosensing Applications.

Willian A Paiva-Marques,Faustino Reyes Gómez,Osvaldo N Oliveira,J Ricardo Mejía-Salazar

doi:10.3390/s20030944

Abstract

There has been growing interest in using strong field enhancement and light localization in plasmonic nanostructures to control the polarization properties of light. Various experimental techniques are now used to fabricate twisted metallic nanoparticles and metasurfaces, where strongly enhanced chiral near-fields are used to intensify circular dichroism (CD) signals. In this review, state-of-the-art strategies to develop such chiral plasmonic nanoparticles and metasurfaces are summarized, with emphasis on the most recent trends for the design and development of functionalizable surfaces. The major objective is to perform enantiomer selection which is relevant in pharmaceutical applications and for biosensing. Enhanced sensing capabilities are key for the design and manufacture of lab-on-a-chip devices, commonly named point-of-care biosensing devices, which are promising for next-generation healthcare systems.

Highlights

Objects whose mirror images cannot be superimposed are named chiral, with our hands being the most universal example
We review here the recent trends in chiral plasmonic systems for enantioselective probing of biomolecules, with emphasis on the limitations of the systems reported so far
The use of concepts and strategies of chiral plasmonics has been shown promising, despite the limitations discussed in this review paper

Summary

Introduction

Objects whose mirror images cannot be superimposed are named chiral, with our hands being the most universal example. This geometrical handedness, called chirality, is ubiquitous in nature and plays a key role in the chemical and biological activity of molecules. Opposite mirror images of a chiral molecule that share the same stoichiometric molecular formula are known as enantiomers, being divided into left- (L) and right-handedness (R), respectively. Geometrically chiral plasmonic structures have been used to tailor and tune the far- and near-field chiroptical responses [25,26,27,28,29,30,31,32,33,34,35,36,37]. An outlook is presented of the application of chiral plasmonics for point-of-care biosensing applications

Plasmonics for Enhanced Chiroptical Effects

Chiral Plasmonic Nanoparticles

Chiral Plasmonic Metasurfaces

Summary and Outlook