title: Experimental demonstration of a novel bio-sensing platform via plasmonic band gap formation in gold nano-patch arrays.
abstract: In this paper we discuss the possibility of implementing a novel bio-sensing platform based on the observation of the shift of the leaky surface plasmon mode that occurs at the edge of the plasmonic band gap of metal gratings, when an analyte is deposited on top of the metallic structure. We report numerical calculations, fabrication and experimental measurements to prove the sensing capability of a two-dimensional array of gold nano-patches in the detection of a small quantity of Isopropyl Alcohol (IPA) deposited on top of sensor surface. The calculated sensitivity of our device approaches a value of 1000 nm/RIU with a corresponding Figure of Merit (FOM) of 222 RIU(-1). The presence of IPA can also be visually estimated by observing a color variation in the diffracted field. We show that color brightness and intensity variations can be ascribed to a change in the aperture size, keeping the periodicity constant, and to different types of analyte deposited on the sample, respectively. Moreover, we demonstrate that unavoidable fabrication imperfections revealed by the presence of rounded corners and surface roughness do not significantly affect device performance.
authors: Dipartimento di Elettrotecnica ed Elettronica, Politecnico di Bari, Via Re David 200, 70125 Bari, Italy. grande@deemail.poliba.it
authors: Marco
authors: M
authors: Grande
authors: Maria Antonietta
authors: MA
authors: Vincenti
authors: Tiziana
authors: T
authors: Stomeo
authors: Giuseppe
authors: G
authors: Morea
authors: Roberto
authors: R
authors: Marani
authors: Valeria
authors: V
authors: Marrocco
authors: Vincenzo
authors: V
authors: Petruzzelli
authors: Antonella
authors: A
authors: D'Orazio
authors: Roberto
authors: R
authors: Cingolani
authors: Massimo
authors: M
authors: De Vittorio
authors: Domenico
authors: D
authors: de Ceglia
authors: Michael
authors: M
authors: Scalora
mesh_terms: D019840:2-Propanol / Q000737:chemistry; D000388:Air; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods*; D003198:Computer Simulation; D006046:Gold / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D012542:Scattering, Radiation; D012825:Silicon / Q000737:chemistry
chemical_list: D006046:Gold; D019840:2-Propanol; D012825:Silicon