Four simple, rapid, and accurate spectrophotometric methods were developed for the simultaneous determination of two food colorants, Carmoisine (E122) and Ponceau 4R (E124), in their binary mixtures and soft drinks. The first method is based on recording the first derivative curves and determining each component using the zero-crossing technique. The second method uses the first derivative of r...

Studies of protein-bound (PB-SH) and nonprotein bound sulfhydryl group (NP-SH) concentrations in tissues under various conditions is a prerequisite to understanding the role of sulfhydryls in living organisms. Many methods have been developed for the measurement of sulfhydryl groups, but these have been concerned chiefly only with the estimation of NP-SH in biological fluids or total SH groups ...

A simple, sensitive and selective method for the determination of bromide in seawater by using a flow injection/stopped-flow detection technique was examined. The detection system was developed for a new kinetic-spectrophotometric determination of bromide in the presence of chloride matrix without any extraction and/or separation. The detection was based on the kinetic effect of bromide on the ...

Sesquiterpene lactones (SLs), mainly those with an activated exocyclic methylene group, are important allergens in Asteraceae (Compositae) plants. As a screening tool, the Compositae mix, consisting of five Asteraceae plant extracts with allergenic potential (feverfew, tansy, arnica, yarrow, and German chamomile) is part of several national patch test baseline series. However, the SL content of...

Flow injection (FI) spectrophotometric method for iron (III) determination using Disodium-1-nitroso-2-naphthol-3,6disulphonate (nitroso-R salt) is performed. It is based on the measurement of Fe(III)-nitroso-R salt complex at 720 nm formed by the reaction between Fe(III) and nitroso-R salt in an acetate buffer solution pH 5. The FI parameters that affect the signal response have been optimized ...

Sensitive visual and micro spectrophotometric methods have been developed for field determination of trace iron in fresh water samples. For the visual method, a water sample (0.45-microm filtrate acidified to 0.1 M HCl) was placed in a glass vial and mixed with a reagent solution containing 1,10-phenanthroline, sodium thiocyanate and 0.1 M HCl. Iron was extracted as pink ferroin thiocyanate wit...

The need to improve pharmacopoeial approaches the standardization of medicinal plant raw materials (MPRMs) and herbal products (HMPs), ensure implementation principle «cross-cutting» in series «medicinal material – phyto-substance product» determine relevance developing new, more rational analysis objects origin. purpose research was theoretical experimental substantiation use reference develop...

In the present work, a sequential injection system with spectrophotometric detection was developed for the determination of free and total sulphur dioxide in wines. It was based on the formation of a coloured product from the reaction among SO2, formaldehyde and pararosaniline. A gas diffusion unit (GDU) was incorporated into the manifold to prevent the wine matrix interference in the spectroph...

We compared electrophoretic evaluation of acid phosphatase isoenzymes with spectrophotometric determination of prostatic acid phosphatase in terms of clinical utility. In all of 33 cases of prostatic carcinoma, an increased prostatic fraction was detected; in nine prostatectomized patients, this fraction returned to normal as measured by either technique. Abnormal spectrophotometric results wer...

A successful prescription is presented for acetylcholinesterase physically adsorbed on to a mesoporous silicon surface, with a promising hydrolytic response towards acetylthiocholine iodide. The catalytic behaviour of the immobilized enzyme was assessed by spectrophotometric bioassay using neostigmine methyl sulfate as a standard acetycholinesterase inhibitor. The surface modification was studi...