title: Enhanced surface plasmon resonance imaging detection of DNA hybridization on periodic gold nanoposts.
abstract: We explore periodic gold nanoposts as substrates for the enhanced surface plasmon resonance imaging (SPRi) detection of DNA hybridization. Rigorous coupled-wave analysis was used to model and design the nanopost-based SPRi biosensor. Arrayed gold nanoposts on gold-coated glass substrate, with various widths and periodicity, were fabricated using electron-beam lithography and characterized with scanning electron and atomic force microscopy. A scanning-angle SPRi apparatus was used to conduct the kinetic analysis of DNA hybridization on nanopost-based sensor surface and assess the corresponding SPR signal amplification. Experimental results showed that both the nanostructure size and period influenced the SPR signal enhancement; the optimized 30 nm height, 50 nm size, and 110 nm period nanoposts provided a fivefold SPR signal amplification compared with the plain 50 nm thick gold film used as control.
authors.affiliation: Biomedical Engineering Department, McGill University, Montreal, Quebec, Canada.
authors.forename: L
authors.initials: L
authors.lastname: Malic
authors.forename: B
authors.initials: B
authors.lastname: Cui
authors.forename: T
authors.initials: T
authors.lastname: Veres
authors.forename: M
authors.initials: M
authors.lastname: Tabrizian
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D004247:DNA; D004277:DNA, Single-Stranded; D006046:Gold; D007089:Image Enhancement / Q000379:methods*; D007700:Kinetics; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D049329:Nanostructures; D009693:Nucleic Acid Hybridization; D020349:Surface Plasmon Resonance / Q000295:instrumentation / Q000379:methods*
chemical_list: D004277:DNA, Single-Stranded; D006046:Gold; D004247:DNA