Izvestiya of Saratov University.
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)


спектрофотометрия

Spectrophotometric determination of some β-lactam antibiotics in their binary mixtures using the method of partial least squares

The method has been proposed for the spectrophotometric determination of antibiotics of the cephalosporin (cefuroxime, ceftriaxone, cefotaxime, cefazolin) and penicillin (amoxicillin) groups using chemometric data processing (method of partial least squares, PLS). The absorption spectra of 24 binary mixtures of “cephalosporin – cephalosporin” and 16 binary mixtures of “cephalosporin – amoxicillin” with various concentrations in the range of 3–27 and 5–140 μg/ml have been recorded.

Colormetric system for monitoring the growth of microalgae Dunaliella salina under laboratory conditions

The brackish microalgae Dunaliella salina, being an extremophilic halophyte, is a promising object for biotechnological production. The aim of this work is to develop a methodology for non-destructive control of the development of a microalgae culture under conditions of balanced growth during periodic cultivation on plates. Before the start of the experiment, the microalgae culture was synchronized. The quantitative content of chlorophylls a and b, as well as carotenoids, was determined spectrophotometrically in alcohol extracts.

Спектрофотометрическое определение суммарного содержания флавоноидов в лекарственных препаратах растительного происхождения

Спектрофотометрическим методом проведено определение суммарного содержания флавоноидов в лекарственных препаратах растительного происхождения. Выбраны оптимальные условия пробоподготовки и спектрофотометрирования.

КОМПЛЕКСООБРАЗОВАНИЕ СЕРЕБРА (I) С АМПИЦИЛЛИНОМ, ОКСАЦИЛЛИНОМ, ЦЕФАЗОЛИНОМ И ЦЕФОТАКСИМОМ В ВОДНЫХ РАСТВОРАХ

Спектрофотометрическим и рН-потенциометрическим мето-
дами в водном растворе на нитратном фоне (KNO3, ? = 0.1,
t = 20 ± 2 °C) изучены комплексные соединения серебра (I) с
ампициллином, оксациллином, цефазолином и цефотаксимом.
Установлены области рН формирования и существования ком-
плексов при заданных концентрациях серебра(I) и лиганда, их
мольный состав. Показано преимущество образования [AgL2]?
комплексов при изменении рН среды; рассчитаны константы
устойчивости комплексов. Определены константы диссоциации

Exploration of Possibilities for Organic Selenides and Dihydroselenochromilium Salt Interaction with Diphenylpicrylhydrazyl

Higher fungi – basidiomycetes play significant role as food and biological subjects for establishing the regularities of the living systems’ operation, development and response to the different-nature effectors impact. Insufficient activity of the living organisms’ antioxidant system interfering the ability of overcoming the negative consequences of oxidative stress (excessive level of free radicals in cells) is believed to be a reason for the organisms aging and death.

The Research of the Behavior of Cefixime in Aquatic and Biological Media by Spectrophotometric Method

The research of behavior of cefixime in biological media was conducted by spectrophotometric method. It was shown that the maximum of light absorption of cefixime against the background of oral fluid is observed at ? = 292 nm and for blood serum at ? = 289 nm. The interval of linear dependence optical density – concentration of cefixime is 3–50 mkg/ml. The optimal conditions of precipitation of proteins in the studied biological media were revealed.