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We propose a new approach to assessing the contamination of tea, coffee, cocoa, and vegetable oils with F-, Cl-, Br- and S-containing organic pesticides and other hazardous anthropogenic and natural compounds at a trace level. The approach ensures the rapid screening of test samples for the total concentration of all halogen and sulfur organic compounds present in the samples. Sample preparation is excluded. The procedure is based on the direct high-temperature oxidative conversion of a test sample under oxygen; the absorption of inorganic salts present in the sample in a reactor; the absorption of the conversion products of organic compounds of the sample, including the analyzed ones, by deionized water with the formation of F–, Cl–, Br– and SO $$_{4}^{{2 - }}$$ anions; and their determination in the absorbate by ion chromatography. This approach ensures the simultaneously reliable determination of all volatile, medium-volatile, and nonvolatile organohalogen and organosulfur compounds present in one sample and, thereby, improves the reliability of detection by eliminating their losses during the analysis.

A methodology is proposed for the highly selective, sensitive, and reliable determination of the total concentration of halogen and sulfur organic compounds in vegetable oils in the presence of inorganic salts, based on the direct high-temperature conversion of an oil sample in a stream of pure oxygen, absorption of inorganic salts in a reactor, absorption of the products of analyte conversion with deionized water to form F–, Cl–, Br–, and S $${\text{O}}_{4}^{{2 - }}$$ anions, and their determination in the absorbate by ion chromatography. An increase in the reliability of the determination of F–, Cl–, and Br– anions is provided by combining the registration of retention times in the direct determination of anions with an analysis of the flow of the same absorbate after the selective removal of F–, Cl–, and Br– anions (together) using corresponding adsorption columns packed with cation exchangers R–Al3+ (for F–) and R–Ag+ (for Cl– and Br–) (possibility of distortion of the determination result of these anions due to potentially coeluted components is excluded). Using the proposed methodology, the total concentration of halogen and sulfur organic compounds is determined in samples of vegetable oils of varying degrees of purity. It ranged from 2 × 10–6 to 6.0 × 10–2% (in terms of element), depending on the sample and element, at a sample volume of 1 μL. A possibility of increasing sample volume by up to 15 times and lowering the limits of detection to 10–7% (in terms of element) is shown.

Isomeric compounds are characterized, on the one hand, by the proximity of the main physicochemical characteristics, including mass, NMR and IR spectra, and on the other hand, by significant differences in properties essential for a human being, for example, reactivity and toxicity. Virtually all known physicochemical methods of analysis are used to study and determine isomers; chromatography–mass spectrometry is among the most effective ones. Mass spectrometric identification includes library search, building the structure of a molecule based on fragmentation patterns for various classes of organic substances, and the use of special methods of ionization, yielding information about the structure of molecules. Chromatographic separation enables the identification of isomeric compounds with identical mass spectra. Information about the presence of specific isomers in their complex mixtures is necessary for making serious arbitral decisions in forensic science, toxicology, or doping analysis. The review discusses examples of using chromatography–mass spectrometry for isomer-specific analysis in antidoping control.

The adsorption of polychlorinated aromatic hydrocarbons on graphitized thermal carbon black was simulated by a molecular-statistical method. The results of calculations were compared with data on chromatographic retention under gas chromatography conditions. A version that took into account the conformational flexibility of molecules was used for polychlorinated biphenyls. Different computational chemistry methods (classical molecular dynamics and semiempirical quantum methods) for evaluating the internal energy of a molecule were considered. It was found that the use of a molecular-statistical method and the AM1 semiempirical method for estimating the internal energy of molecules makes it possible to correctly predict the order of elution of isomeric dichlorobiphenyls. It was demonstrated that this approach can be used to confirm the assignment of peaks in a chromatogram to particular isomers.

Mass spectrometry and chromatography are used to study the decomposition products of Teflon mixtures of the “Fluralite-4” brand with magnesium, tungsten, and titanium, activated by mechanochemistry. The temperature and energy parameters of water and carbon dioxide release are determined, volatile products of Teflon depolymerization are detected and identified, i.e., tetrafluoroethylene, trifluoromethylene, trifluoroethylene. It is shown that the introduction of metal mixtures in the composition significantly affects the decomposition processes of Teflon.

The problem of determining the most toxic halogen- and sulfur-containing organic compounds at the trace level in different media by rapid screening based on the high-temperature oxidative conversion of a sample in combination with ion chromatography being solved at the Department of Analytical Chemistry of Moscow State University is considered. This approach ensures the rapid control of the total content of organic compounds containing F, Cl, Br, and S atoms in a molecule, regardless of the availability of data on their presence in the sample.

The retention of glycine-based peptides on a Hypercarb carbon adsorbent is studied by reversed-phase HPLC. In the reaction mixture obtained in the synthesis of polyglycines, ions corresponding to both linear and cyclic peptides are detected by electrospray ionization mass spectrometry. Characteristics of the retention of the components are determined on varying the composition of the mobile phase in the isocratic mode. It is shown that some of the detected ions are fragmented ions of linear polyglycines rather than protonated individual cyclic peptides, which complicated identification. The presence of five linear polyglycines as well as cyclodiglycine in the test mixture is confirmed.

The application of mass spectrometry to the detection of m-nitrobenzoic and 3,5-dinitrobenzoic acids and their salts on the surface of construction materials used in rocketry is described. Analytes are washed with acetonitrile from the studied surface and then analyzed by HPLC−MS with electrospray ionization or the matrix assisted laser desorption/ionization (MALDI). For electrospray ionization, the limit of detection is 6 μg/L and for MALDI ionization, 2 μg/L. The MALDI technique also ensures the direct investigation of samples without washing out; in this case, mass spectra can be visualized by constructing 2D diagrams of the distribution of nitrobenzoic acids over the surface.

The products of conversion of 1,1-dimethylhydrazine after contact with the surface of AMg-6 alloy, which is a model of construction materials that contact with rocket fuel components, were characterized by use of chromatographic and mass-spectrometric methods. Alkyl phthalates, the homologues of triphenyl phosphate, and numerous polymer-homologues related to acetone condensation products were detected in acetone extracts taken from the test surfaces. The presence of such products makes it possible to identify fuel components that contacted with the construction materials; this is important for the utilization of the detachable parts of launch vehicles.

RIB-Nitrite-Test and Sorbfil-Nitrite-Test strips were developed for determining nitrite ions in water samples and foodstuffs by a reaction similar to the Griess reaction. Stable and noncarcinogenic 3-hydroxy-7,8-benzo-1,2,3,4-tetrahydroquinoline was used as an azo component adsorbed in the reagent paper zone on a polymeric support or on a Sorbfil plate sealed in a transparent polymeric film. Performance characteristics were evaluated by a statistical method for visual test procedures for the detection and determination of NO2− using two different test strips. The determination limit was 0.54 and 0.09 mg/L, and the detection limit was 0.50 and 0.08 mg/L, respectively.