PURPOSE To characterize the intrinsic fluorescence (autofluorescence) of the human ocular fundus with regard to its excitation and emission spectra, age relationship, retinal location, and topography, and to identify the dominant fluorophore among the fundus layers. METHODS Using a novel fundus spectrophotometer, fluorescence measurements were made at 7 degrees temporal to the fovea and at th...

We present computationally efficient and accurate semiempirical models of light transfer for real-time analysis of multilayer fluorescing media exposed to normally incident excitation light. The model accounts for absorption and strong forward scattering as well as for internal reflection at the interface between the medium and the surrounding air. The absorption and scattering coefficients are...

europium (eu) doped zno microsphere based nano-sheets were synthesized through hydrothermal method. effects of different concentrations of europium on structural and optical properties of zno nano-sheets were investigated in detail. prepared un-doped and eu-doped zno samples were characterized using x-ray diffraction (xrd), energy dispersive x-ray spectroscopy (edx), scanning electron microscop...

Antibody-conjugated fluorospheres (ACF) were used to phenotype murine leukocytes by flow cytometric analysis. Multicolor immunofluoresence (beyond simultaneous 4-color analysis) is limited by the availability of specific antibody-fluorochrome chrome conjugates and even further restricted by the spectral emission overlap of many of the fluorochromes when used in combination. Fluorospheres posses...

The differentiation of porcelain from tooh using fluorescence emission was investigated as a basic research for the visual detection of porcelain-restored teeth in mass dental health examinations. The fluorescence spectra were taken from the extracted human maxillary central incisors and five types of porcelain by excitation using the light 380-470 nm. There was a clear difference in fluorescen...

A shift in the wavelength of maximum fluorescence emission toward higher wavelengths, caused by a shift in the excitation wavelength toward the red edge of the absorption band, is termed the Red Edge Excitation Shift (REES). This effect is mostly observed with polar fluorophores in motionally restricted media such as very viscous solutions or condensed phases. In this paper, we report the red e...

CdSe nanocrystals and aggregates of an aryleneethynylene derivative are assembled into a hybrid thin film with dual fluorescence from both fluorophores. Under continuous excitation, the molecules exhibit anticorrelated intensity variations, which become periodic at low temperature. We attribute this to structure-dependent aggregation-induced emission derivative, impacts rate excitation energy t...

The tumor-localizing photosensitizer hematoporphyrin derivative (HPD) is shown to undergo a simultaneous two-photon excitation into the near-ultraviolet Soret band system upon intense laser irradiation at 750 nm, a spectral region where there is no significant HPD one-photon absorbance in aqueous solution. Subsequent to this excitation, internal conversion and vibrational relaxation occur, resu...

Structure-activity studies of tetramethinemerocyanine fluorophores enabled the synthesis of novel dyes which showed spectral changes during reversible, calcium-dependent association with calmodulin. These spectral changes were greatly enhanced in dyes with a quaternary nitrogen and specifically placed hydrophobic chains. One such dye was covalently attached to calmodulin, producing a calmodulin...

Introduction Fluorescence is a natural molecular phenomenon that can be described by the absorption of light by a molecule at one wavelength followed by the emission of light at a longer wavelength [1], [2]. The fluorescence can be characterised by its excitation and emission spectra, quantum yield, polarisation state of the emission and also by the characteristic fluorescence decay following a...