Detecting Antibody–Antigen Interactions with Chiral Plasmons: Factors Influencing Chiral Plasmonic Sensing

Chiral near fields possessing enhanced asymmetry (superchirality), created by the interaction of light with (chiral) nanostructures, potentially provide a route to novel sensing and metrology technologies for biophysical applications. However, mechanisms which these lead detection chiral media is still poorly understood. Using combination numerical modelling experimental measurements on an antibody-antigen exemplar system we illustrate important factors that influence efficacy sensing. We demonstrate localised lattice resonances display enantiomeric sensitivity. only exhibit strong dependency structure detected. This can be attributed ability birefringent layers strongly modify properties acting as sink / source optical chirality, hence alter inductive coupling between nanostructure elements. In addition, highlight how surface morphology defects may amplify capabilities plasmonic modes mediating coupling.