Resonant Dielectric Nanostructures for Biosensing

We investigate the electromagnetic resonance behavior of dielectric nanorod arrays for field induced fluorescence enhancement and their application in the optical biosensing technology.

ZnO and SiO2 nanopillar arrays were fabricated with innovative lithographic and replication processes. Reproducible high quality nanostructures can also be obtained for different structural parameters on glass slides. The surface of the structures have been modified in order to enhance the quantity and favor the adhesion of the labeled antibody on the nanopillars. A fluorescence measurement technique has been designed and built to characterize the optical properties of the manufactured samples. The primary advantage of this system is the ability to modify the incident excitation angle which is a crucial parameter for determination of the resonant angle. The measurements have shown a strong fluorescence enhancement. Theoretical understanding is achieved by extensive electromagnetic simulations using 3D finite-element methods.