AIMS To develop a fluorimetric method for the estimation of urinary aldosterone; to establish a normal range in 24 hour and overnight urine samples; and to investigate the use of overnight urines for detecting hyperaldosteronism. METHODS Essential steps include hydrolysis of the 18 conjugate to release aldosterone and its oxidation with Benedict's solution, followed by thin-layer chromatograp...

By combining laser fluorimetry with high pressure liquid chromatography, we are able to detect and quantitate the naturally fluorescent mycotoxin, zearalenone, in contaminated corn samples. Experiments with zearalenone standards show a linear fluorimeter response over four orders of magnitude with a detection limit of 300 pg zearalenone injected onto a C,8 reverse phase column. The corn samples...

Urine contains a variety of organic and inorganic chemicals including a number of natural fluorophores. Most of them are formed by tryptophan metabolites. But there are also metabolites of riboflavin, catecholamines and porphyrins. The alternation in the autofluorescence of urine and the alternation in the concentration of these substances are developed by both physiological and pathological ch...

The dielectric relaxation (DR) of human serum albumin (HSA) was studied by the method of phase-fluorometry. The protein environment of the single tryptophan in HSA shows a relatively low-speed DR of sub-ns characteristic time. This relaxation can be measured as a decaying red-shift of the time-resolved fluorescence emission spectra. The details of calculations of time-emission matrices (TEM) an...

nanoDSF, the miniaturized differential scanning fluorimetry technology, is a revolutionary method to determine the thermostability of proteins by following changes in their intrinsic fluorescence. In this comparative study, the Prometheus NT.48 was used to determine the thermal stability of the membrane esterase PA2949 from Pseudomonas aeruginosa in presence of various detergents. The detergent...

Until now, there are few information on vitamin B2 concentration variability in milk. In this study, a novel analytical method to quantify total milk was developed and applied 676 samples. parallel, spectral analysis (colorimetry near infrared spectroscopy) were performed develop prediction models of The includes an acid enzymatic extraction followed by quantification Ultra High Performance Liq...

riboflavin and protoporphyrin ix are two molecules that participate in oxidation and reduction reactions in the living cell. changing some functional groups of riboflavin and protoporphyrin ix can provide compounds with self-assembled monolayer properties with wide applications in designing the molecular electronic devices. in this study, the amphiphilic structure of riboflavin and protoporphyr...