We have developed a portable multiexcitation dye laser system pumped by a 308 nm excimer laser, which can collect fluorescence spectra at 11 excitation wavelengths and a white light reflectance spectrum in less than 200 ms. The system is designed to be used in a hospital setting for in vivo tissue analysis based on fluorescence and reflectance spectroscopy. A specially designed optical fiber pr...

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...

a simple and rapid microextraction procedure based on the application of magnetic nanoparticles and hydrophobic 1-hexylpyridinium hexafluorophosphate [hpy][pf6] ionic liquid (il) was applied to trace determination of gatifloxacin. a mixture of [hpy][pf6] and magnetic nanoparticles was injected into the sample solution containing the analyse of interest and a cloudy solution was formed. after ce...

A sensitive fluorimetric assay based on DNA binding of the fluorescent dye Hoechst 33258 was developed to quantitate cell numbers in microtiter plates. The cells were fixed and incubated with the dye solution. The bound dye was extracted with ethanol and fluorescence was measured in a spectrofluorimeter. The method is sensitive for as little as a thousand cells and is particularly useful for th...

Fluorescence is a proven tool in all fields of knowledge, including biology and medicine. A significant obstacle in its use is the nonlinearity of the dependence of the fluorescence intensity on fluorophore concentration that is caused by the so-called primary inner filter effect. The existing methods for correcting the fluorescence intensity are hard to implement in practice; thus, it is gener...


An investigation of light scattering of non-imprinted poly methacrylic acid-co-ethylene glycol dimethacrylate (PMAA-co-EGDMA) submicron particles (300±5 nm) in aqueous suspension before and after 17β-estradiol (E2) binding was conducted by using a spectrofluorimeter. An optimal excitation wavelength to determine Mie scattering from these submicron particles was 725±1 nm for the highest intensi...

A quick and very sensitive method is proposed for the determination of the insecticide carbaryl, following transformation in 1-naphthol, using solid-phase fluorescence excited by a pulsed nitrogen laser and detected with a charge-coupled device. Carbaryl is hydrolized in an alkaline medium resulting in 1-naphthol. This hydrolysis product is fixed on QAE Sephadex A-25 gel at pH 11.20. The fluore...

Fluorescence spectroscopy was examined as a potential technique for identification and classification of bacterial pathogens. Colonies of Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi, and Klebsiella pneumoniae on agar plates were measured directly using a laboratory spectrofluorimeter coupled with optical fiber. Steady state fluorescence spectra were collected following excit...

Nucleic acids can form large particle complexes with protamine sulfate by electrostatic forces, which results in strong light scattering. Based on this, a nephelometric method is described for sensitive and convenient determination of nucleic acids with protamine sulfate by using a common spectrofluorimeter. Maximum light scattering is produced in the range of pH 2.2-4.4 with the same excitatio...