title: Fabrication of large-area ordered and reproducible nanostructures for SERS biosensor application.
abstract: We propose a large-area SERS device with efficient fluorescence quenching capability. The substrate is based on anodic porous alumina templates with various pore size and wall thickness as small as 15 and 36 nm, respectively. The nano-patterned SERS substrate, with excellent control and reproducibility of plasmon-polaritons generation, shows very efficient enhanced Raman signal in the presence of intrinsically fluorescent molecules such as cresyl violet, rhodamine, and green fluorescent protein. This work demonstrates that, when the nanostructures are properly designed and fabricated, Raman and fluorescence spectroscopy can be used in combination in order to obtain complementary molecular informations. Theoretical simulation shows excellent agreement with the experimental findings. The enhancement factor is found to be 10(3)-10(4), with respect to flat gold surface when the molecules are supposed to be closely packed, with considerable fluorescence suppression, showing a promising disposable biosensor.
authors.affiliation: Italian Institute of Technology, via Morego 30, I-16163 Genoa, Italy. gobind.das@iit.it
authors.forename: Gobind
authors.initials: G
authors.lastname: Das
authors.forename: Niranjan
authors.initials: N
authors.lastname: Patra
authors.forename: Anisha
authors.initials: A
authors.lastname: Gopalakrishnan
authors.forename: Remo Proietti
authors.initials: RP
authors.lastname: Zaccaria
authors.forename: Andrea
authors.initials: A
authors.lastname: Toma
authors.forename: Sanjay
authors.initials: S
authors.lastname: Thorat
authors.forename: Enzo
authors.initials: E
authors.lastname: Di Fabrizio
authors.forename: Alberto
authors.initials: A
authors.lastname: Diaspro
authors.forename: Marco
authors.initials: M
authors.lastname: Salerno
mesh_terms: D048588:Benzoxazines; D015374:Biosensing Techniques; D005456:Fluorescent Dyes / Q000737:chemistry; D049452:Green Fluorescent Proteins / Q000737:chemistry; D010078:Oxazines / Q000737:chemistry; D015203:Reproducibility of Results; D012235:Rhodamines / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013059:Spectrum Analysis, Raman
chemical_list: D048588:Benzoxazines; D005456:Fluorescent Dyes; D010078:Oxazines; D012235:Rhodamines; D049452:Green Fluorescent Proteins; C028911:cresyl violet