Tunable fluorescence from patterned silver nano-island arrays for sensitive sub-cell imaging

Abstract

Surface-enhanced fluorescence, a burgeoning technique in biological detection, provides largely enhanced fluorescence signal by exciting localized surfaces plasmons resonance with fluorescent dyes. Nanostructure and surroundings brings great impact on the emission signal, however, insufficient physics about the process limits further improvement on the nanostructure design. In this study, optical properties of Rhodamin-6G molecules on patterned silver nano-island arrays are tailored by precisely controlling the distance between the dyes and silver arrays. The fluorescence signal depends on the distance and the largest enhancement of 10 folds is achieved when the distance is 10 nm. The results are theoretically corroborated by finite difference time domain simulation and applied to cytoskeleton fluorescence imaging using phalloidin-fluorescein isothiocyanate. Our study provides insights into the physical mechanisms associated with the fluorescence enhancement and quenching, and our experiments suggest potential applications to high-sensitivity sub-cell imaging.

Large-Scale Inhomogeneous Fluorescence Plasmonic Silver Chips: Origin and Mechanism

“…However, the large-scale plasmonic chips prepared by the methods of vacuum evaporation, chemical reduction, or colloidal deposition usually exhibit the relatively low fluorescence enhancements, ranging from 5-to 50-fold. [18][19][20][21][22][23][24][25][26] Recently, one of us proposed a seed-mediated growth procedure for the fabrication of large-scale plasmonic gold chips, 27 in which the inter-island gap distances are inhomogeneous (non-uniform). Moreover, the chips exhibit strong fluorescence enhancement (up to 100-fold) 8 as well as the distinct dependence of fluorescence enhancement on the average gap distance.…”

Plasmon-Enhanced Fluorescence of Carbon Nanodots in Gold Nanoslit Cavities

“…For many of these applications, it is desirable to enhance the fluorescence to obtain a greater signal from few samples. Surface plasmons (SPs) (1,2) on subwavelength nanostructured surfaces were found to be capable of fluorescence enhancement. (3) The optical phenomena of SPs lie considerably in the conductive surfaces through manipulating the geometry of subwavelength apertures with a periodic structure.…”

“…For many of these applications, it is desirable to enhance the fluorescence to obtain a greater signal from few samples. Surface plasmons (SPs) , on subwavelength nanostructured surfaces were found to be capable of fluorescence enhancement . The optical phenomena of SPs lie considerably in the conductive surfaces through manipulating the geometry of subwavelength apertures with a periodic structure. , The plasmonic-enhanced fluorescence results in a variety of applications, such as biodetection and biosensing schemes. , Specifically, many cancer biomarkers, hormones, allergens, and proteins have been detected by SP resonance (SPR) biosensors with high accuracy and sensitivity .…”