A fast 3-D optical imaging method with use of exogenous fluorescence agent is proposed and demonstrated by simulation in a model tissue. After administration of fluorescent agent, ultrashort near-infrared laser pulses are used to illuminate the tissue and excite fluorescence emission. The transient fluorescence signals are detected on the tissue boundaries and employed to reconstruct a 3-D imag...

A new lead fluoroborate glass (PbO-PbF2-B2O3) doped with ytterbium (Yb:PbFB) is presented. Samples with different concentrations of Yb3+ were produced and had their emission cross-sections, fluorescence lifetimes and minimum pump intensities determined. They have high refractive index of 2.2 and a density of 4.4 g/cm3. For a doping level of 1.153x1020 ions/cm3, the fluorescence lifetime, after ...

glucose 6-phosphate dehydrogenase (g6pd) was purified from streptomyces aureofaciens and inactivated with butanedione and diethylpyrocarbonate. incubation of the enzyme with butanedione resulted in a rapid activity loss (80%) within 5 min, followed by a slow phase using a molar ratio to enzyme concentration of 100. fluorescence studies showed a conformational change in the butanedione-modified ...

Fluorescence quenching spectrometry was applied to study the interactions between gold colloidal nanoparticles and alpha-fetoprotein (AFP). Experimental results show that the gold nanoparticles can quench the fluorescence emission of adsorbed AFP effectively. Furthermore, the intensity of fluorescence emission peak decreases monotonously with the increasing gold nanoparticles content. A mechani...

The emission anisotropy spectra, r,(λ ) of p-cyano-dimethylaniline (CDMA) and p-cyano-diethylaniline (CDEA) in PVA films are temperature dependent. At 296 K a characteristic dependence of r,(λ ) on the absorption (A), short emission (SE) and long emission (LE) band, responsible for the total emission of fluorescence and phosphorescence is observed. On temperature enhancement to 355 K and next t...

Optical antennas made of metallic nanostructures dramatically enhance single-molecule fluorescence to boost the detection sensitivity. Moreover, emission properties detected at the optical far field are dictated by the antenna. Here we study the emission from molecule-antenna hybrids by means of super-resolution localization and defocused imaging. Whereas gold nanorods make single-crystal viole...

This paper presents a unique optical technique that utilizes the reabsorption and emission of two fluorescent dyes to accurately measure film thickness while minimizing errors caused by variations in illumination intensity and surface reflectivity. Combinations of dyes are selected that exhibit a high degree of emission reabsorption and each dye concentration is adjusted to create an optically ...

A butterfly-shaped pyrene derivative of cholesterol, namely, N,N'-(ethane-1,2-diyl)-bis(N-(2-(chol-amino)ethyl)pyrene-1-sulfonamide) (ECPS), has been designed and synthesized. Solvent effect studies revealed that in good solvents such as n-hexane, benzene, and 1,4-dioxane, the profile of the fluorescence emission of the compound is characterized by pyrene monomer emission, but in poor solvent s...

A new method in differentiation of chiral molecules is reported based on the fluorescence quenching of functionalized CdS quantum dots (CdS-QDs) as nanosensor by differing in the chirality of functionalization species. The chemically functionalized CdS-QDs with strong yellow emission were prepared using chiral L-cysteine (L-Cyst) and D-cysteine (D-Cyst) molecules. Then, the functionalized CdS-Q...