The results of determination of trace quantites of selenium in various commercial natural fruit juices by three independent methods: atomic absorption spectrometry (AAS), spectrophotometry (UV-VIS) and spectrofluorometry (SF) were presented. The level of selenium in any of the analysed samples of fruit juices did not exceed the WHO recommended level of 0.010 mg/l for drinking water.

attempts to obtain experimental values for the kinetic parameters of phenanthridine oxidation by guinea pig or rabbit liver aldehyde oxidase using common spectrophotometric methods have not been successful due to a lower limit of detection. in the present study, a new spectrofluorimetric assay in combination with a multivariate calibration method for enzymatic kinetic study of aldehyde oxidase ...

We report a rapid, simple, and sensitive spectrofluorometric procedure for total serum or plasma tryptophan. Plasma deproteinization, tryptophan extraction, and pH optimization are all carried out with a buffered cellulose/ethanol reagent. The fluorescence is measured at an emission wavelength of 350 nm, on excitation of 290 nm. Tryptophan fluorescence relative to concentration is linear up to ...

Measuring spray retention by plant leaves was the aim of many experiments in plant protection researches. Different methods have been used to measure spray proportion retained on vegetative surfaces, such as chemical methods using dyes and other methods using image analysis. We conducted Laboratory studies in order to validate the effectiveness of using high-speed imaging method developed by Ma...

Standard ISO method for chlorophyll a quantification (extraction into ethanol, spectrophotometrical quantification at 665 and 750 nm), spectrofluorometry (reader for 96 wells, excitation 410 nm, emission 670 nm), and a submersible fluorescence probe for in situ phytoplankton quantification (excitation 410, 525, 570, 590, and 610 nm, emission 685 nm) were compared in different freshwater environ...

The purpose of this study was to compare in a laboratory experiment, a suite of methods developed to track viable bacteria during field transport experiments. The criteria for development and selection of these methods included: (1) the ability to track bacteria within the environment from which they were isolated; (2) the lack of any effect upon the viability or the transport characteristics o...

A novel dual-function material was synthesized by anchoring a molecularly imprinted polymer (MIP) layer on CdTe/ZnS quantum dots (QDs) using a sol-gel with surface imprinting. The material exhibited highly selective and sensitive determination of ractopamine (RAC) through spectrofluorometry and solid-phase extraction (SPE) coupled with high performance liquid chromatography (HPLC). A series of ...