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


Microextraction preconcentration with nonionic surfactants and colorometric determination of phenol

The extraction of the tungsten blue complex formed by the reaction of phenol with Folin-Ciocalteu reagent (FCR) in the presence of a nonionic surfactant Triton X-100 in alkaline medium using the methodology of micellar extraction based on «clouding point» has been studied for the fi rst time. Aqueous solutions of sodium carbonate and sodium sulfate were used to create pH and as a desalting agent.

Prospects for the use of polymer-containing materials and sorbents for membrane ultrafi ltration, sorption and concentration of nucleic acids from aqueous media. A review

Unlike antibiotics and heavy metals, nucleic acids exist in the aquatic environment as a part of prokaryotic and eukaryotic microorganisms (bacteria, fungi, etc.) rather than in a free form. In this regard, the most important primary stage of sample preparation of an object for the quantitative analysis of DNA and RNA in natural and wastewaters includes membrane ultrafi ltration of an aqueous sample, followed by its sorption preconcentration on a solid phase carrier.


Рассмотрен аналитический метод – «экстракция в точке помут-
нения» применительно к концентрированию и выделению соеди-
нений свинца из различных матриц. Дана характеристика при-
меняемых для этих целей ПАВ. Оценены факторы, влияющие
на коэффициент, константу распределения и коэффициент кон-
центрирования хелатов в мицеллярные фазы ПАВ. Дана срав-
нительная характеристика лигандов-комплексообразоват елей,
применяемых для мицеллярной концентрации ионов свинца.

Preconcentration of Е110 and Е124 Food Azodyes on Magnetite Nanoparticles Modified by CTAB

Synthetic azodyes are widely used in paint, textile, plastic, and food, beverage, and leather, cosmetic, pharmaceutical and paper industries to make products more visually attractive to consumers. Therefore, they are also the components of waste waters and should be removed due to their potential risk to human health. Many techniques have been employed to eliminate dyes from waste water and do to preconcen- tration before analysis in food or beverage objects.

Pre-Concentration and Extraction of Samarium Isotopes by Precipitation of Slightly Soluble Hydroxides and Fluorides of Metals

The comparison and assessment of the efficiency of using the precipitation of sparingly soluble metal hydroxides and fluorides for the extraction and pre-concentration of samarium isotopes from the solution simulating acidic leachate of the soil were made. It was shown that the precipitation of samarium isotopes was achieved quantitatively at the pH of about 7 and the co-precipitation of alkaline and alkaline earth elements did not exceed 20%.

Determination of thymol with micellar extraction preconcentration

For the efficient preconcentration of azo compounds – products of the interaction of 4-nitrophenyldiazonium with thymol, a system 4-nitroaniline (4-NA) – NO2 - – Triton X-100 – NaOH – ethanol has been proposed. The optimal conditions for the formation of micellarsaturated phases of the system under study have been established: 3. 10-4 M 4-NA – 3. 10-4 M NO2 - – 5% Triton X-100 – 2.8 M NaOH – 10 vol. % С2Н5ОН. A spectrophotometric study of the above system has been carried out.