The potential of variable angle synchronous spectroscopy (VASS) for fluorescent mixtures resolution was assessed and compared with the rank annihilation method (RAM). For this purpose, a set of excitation-emission matrices from three standard cyclodextrin fluorescence-enhanced solutions of the pesticides aminocarb, carbendazim and coumatetralyl and a mixture of them was obtained. Careful select...

ĥe fluorescence properties of 3-hydroxyflavone and 2,5-bis(2-benzoxazolyl)hydroquinone have been investigated in solid argon matrices a t 15 K. In both cases dominant emission from the tautomeric form of the molecules is observed. The excitation spectra of this fluorescence a n d a weak fluorescence at shorter wavelength show that the latter is due to molecules with a different ground state, pr...

A multi-spectral fluorescence imaging technique was used to detect defective cherry tomatoes. The fluorescence excitation and emission matrix was used to measure for defects, sound surface and stem areas to determine the optimal fluorescence excitation and emission wavelengths for discrimination. Two-way ANOVA revealed the optimal excitation wavelength for detecting defect areas was 410 nm. Pri...

Reflectance and fluorescence spectroscopies have shown great promise for early detection of epithelial dysplasia. We have developed a clinical reflectance spectrofluorimeter for multimodal spectroscopic diagnosis of epithelial dysplasia. This clinical instrument, the FastEEM, collects white light reflectance and fluorescence excitation-emission matrices (EEM's) within a fraction of a second. In...

The application of trilinear decomposition (TLD) to the analysis of fluorescence excitation-emission matrices of mixtures of polycyclic aromatic hydrocarbons (PAHs) is described. The variables constituting the third-order tensor are excitation wavelength, emission wavelength, and concentration of a fluorescence quencher (nitromethane). The addition of a quencher to PAH mixtures selectively redu...

The relaxation of electronically excited atomic manganese isolated in solid rare gas matrices is observed from recorded emission spectra, to be strongly site specific. z 6P state excitation of Mn atoms isolated in the red absorption site in Ar and Kr produces narrow a 4D and a 6D state emissions while blue-site excitation produces z 6P state fluorescence and broadened a 4D and a 6D emissions. M...

This study describes a simple and rapid approach of monitoring ibuprofen (IBP). Unfolded principal component analysis-artificial neural network (UPCA-ANN) and excitation-emission spectra resulted from spectrofluorimetry method were combined to develop new model in the determination of IBF in human serum samples. Fluorescence landscapes with excitation wavelengths from 235 to 265 nm and emission...

This study describes a simple and rapid approach of monitoring ibuprofen (IBP). Unfolded principal component analysis-artificial neural network (UPCA-ANN) and excitation-emission spectra resulted from spectrofluorimetry method were combined to develop new model in the determination of IBF in human serum samples. Fluorescence landscapes with excitation wavelengths from 235 to 265 nm and emission...

Fluorescence spectroscopy is a promising technology for detection of epithelial precancers and cancers. While age and menopausal status influence measurements in the cervix, other variables do not significantly affect the diagnosis. In this study we examine probe pressure as a variable. A fiber optic probe to measure fluorescence spectra at different calibrated levels of pressure was designed a...

Dipicolinic acid (DPA) and the Ca2+ complex of DPA (CaDPA) are major chemical components of bacterial spores. With fluorescence being considered for the detection and identification of spores, it is important to understand the optical properties of the major components of the spores. We report in some detail on the room-temperature fluorescence excitation and emission spectra of DPA and its cal...