We study the nature of fluorescence scattering by a radiating fluorophore placed near a metal nanoparticle with the finite-difference time-domain method. Angle-resolved light-scattering distributions are contrasted with those that result when ordinary plane waves are scattered by the nanoparticle. For certain sized nanoparticles and fluorophore dipoles oriented parallel to the metal surface, we...

Single-molecule localization microscopy (SMLM) image quality and resolution strongly depend on the photoswitching properties of fluorophores used for sample labeling. Development of fluorophores with optimized photoswitching will considerably improve SMLM spatial and spectral resolution. Currently, evaluating fluorophore photoswitching requires protein-conjugation before assessment mandating sp...

A fluorophore consisting of two fluorescent moieties could display unusual optical behaviors that are unattainable in a single-fluorophore compound. Herein we reported two ‘‘dual-fluorophore’’ dyes: DNSlinked tetraphenylethene demonstrates bright aggregation-induced emission, while NBD-linked tetraphenylethene exhibits aggregationcaused quenching. Our results have important implications for eng...

In just three years, the green fluorescent protein (GFP) from the jellyfish Aequorea victoria has vaulted from obscurity to become one of the most widely studied and exploited proteins in biochemistry and cell biology. Its amazing ability to generate a highly visible, efficiently emitting internal fluorophore is both intrinsically fascinating and tremendously valuable. High-resolution crystal s...

We demonstrate highly efficient evanescent-wave detection of fluorophore-labeled biomolecules in aqueous solutions positioned in the air holes of the microstructured part of a photonic crystal fiber. The air-suspended silica structures located between three neighboring air holes in the cladding crystal guide light with a large fraction of the optical field penetrating into the sample even at wa...

Fluorophore labeling of proteins while preserving native functions is essential for bulk Förster resonance energy transfer (FRET) interaction and single molecule imaging analysis. Here we describe a versatile, efficient, specific, irreversible, gentle and low-cost method for labeling proteins with fluorophores that appears substantially more robust than a similar but chemically distinct procedu...

In this work we report on the so-called plasmonic enhancement effect, whereby the presence of metallic surfaces or particles in the vicinity of a fluorophore can dramatically alter the fluorescence emission and absorption properties of a fluorophore. The effect, which is associated with the surface plasmon resonance of the metallic surface, depends on parameters such as metal type, particle siz...

Light-emitting electrochemical cells (LECs) are an easy-to-fabricate electroluminescent device, which in its simplest manifestation comprises electroluminescence organic fluorophore and electrolytes as the active layer sandwiched between two electrodes. The LEC exhibits poor operational stability, thermal stability of electrolyte is a major cause instability. Because most utilized (polymer ioni...

The development of a dual probe that provides ratiometric measurements of fluid viscosity is described. The design is based on coupling of a primary fluorophore with viscosity-independent fluorescence emission (blue unit) with a secondary fluorophore that exhibits viscosity-sensitive fluorescent emission quantum yield (red unit). Excitation of the secondary fluorophore can be achieved via Reson...