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The development of rapid chromatographic procedures is of utmost relevance to analytical laboratories since the modern pharmaceutical business is continually developing faster and more precise methods of drug discovery, development, distribution, and monitoring. Comprehensive two-dimensional (2D) chromatography is being developed as a tool to address challenges in the analysis of complex materials. Complex sample analyses may yield data that is challenging to quickly and accurately process. Here, chemometric analysis of data has shown to be the most fruitful and illuminating method. There are several applications for the determination of organic chemicals in samples with varying matrices. Gas/liquid chromatographic techniques are used for the bulk of organic chemical determinations. Therefore, it is crucial that these processes have minimal effects on the natural world. The collection and processing of samples, chromatographic separation, and final determination might all have less environmental impact if chromatographic methods were used. In both GC and LC, multidimensional separation methods may be used to improve the environmental friendliness of the analysis. The study describes 2D chromatographic techniques for GC-MS, 2D-LC, 2D-GC, 2D-CE, FTIR, and 2D-IR. Moreover, their advantages, challenges, and previous analytical data are also covered. [ABSTRACT FROM AUTHOR]

A rapid procedure for the determination of phenol and cresol isomers in drinking, sea, and polluted domestic wastewater is developed based on a single-stage extraction of analytes by extractive freezing-out under sample centrifugation conditions. In combination with gas chromatography, the procedure provides the minimum detection limits for each of phenols in 10 mL of water at a level of 0.0005 µg/mL. The duration of sample preparation does not exceed 30 min; the consumption of the ethoxyethane extractant is 1.4 mL. In comparison with liquid–liquid and solid-phase extraction traditionally used at the stage of sample preparation, the proposed procedure is simpler and more environmentally friendly. The stages of filtering samples and dehydrating extracts are excluded; the amount of chemical glassware is minimized. [ABSTRACT FROM AUTHOR]

This review is devoted to the consideration of prospects and directions for the development of methods and approaches to the analysis of high-purity industrial gases and volatile hydrides, chlorides, fluorides, and organoelement compounds with natural and isotopically enriched compositions. The currently known capabilities for the determination of impurities in them using mass spectrometry, IR spectroscopy, gas chromatography, and chromatography–mass spectrometry are analyzed. [ABSTRACT FROM AUTHOR]

Luminescent quantum dots (QDs) of I–III–VI2 semiconductors present a new class of luminescence materials that combine unique optical and electronic properties while exhibiting low toxicity compared to conventional cadmium-based QDs. Advances in the colloidal synthesis of ternary QDs have been used to develop fluorescence chemical and biological sensors for the detection of various analytes. The review covers the main approaches to synthesizing QDs of the I–III–VI2 structure, the features of their structure and properties, and current trends in their use as low-toxic luminescent labels in biomedicine and chemical analysis. [ABSTRACT FROM AUTHOR]

We substantiate an approach to the creation of a device for establishing gross adulteration of gasoline by replacing their part with fuel with a lower octane number and demonstrate the application of mass-sensitive sensor electrodes using the specific features of the adsorption of volatile compounds from the headspace of gasoline with different octane numbers (AI-92, AI-95) by the sensor modifiers. The results helped select three coatings most sensitive and selective to traces, differently adsorbing compounds of the highly volatile gasoline fraction. Simple recorded and calculated signals of the "electronic nose" SΣ, Sτ, A(i/j), AS(τ1/τ2), giving information on the composition of a gasoline sample and assessing the change in composition on adding fuel of a different type or brand, are proposed. The algorithm for calculating and making a decision is simple and can be programmed into the microcircuit of a mobile device. Introducing an "electronic nose" gas analyzer based on piezoelectric balances into the fuel quality control system is helpful to reveal the facts of adulteration of high-octane gasoline by adding gasoline with a lower octane number and to estimate the amount of the additive. A method is developed for in situ analysis performed by experts or untrained users; it readily gives an assessment of adulteration with an additive concentration of 6 to 50 vol % with an error of no more than 12%. [ABSTRACT FROM AUTHOR]