An example of annotation formatting

An abstract is a stand-alone, informative text that allows the reader to evaluate the content, scientific novelty, and practical significance of the study without consulting the full text of the article. The abstract should be logically complete, informative, and understandable outside the context of the main text.

The recommended length of the abstract is 150–250 words in Russian. The English abstract should be a correct and complete translation of the Russian version, without abbreviations or semantic differences.

The content of the abstract should reflect the structure of the article and include the following elements:

Relevance of the research - justification of the significance of the topic, formulation of the scientific problem;
The purpose of the study is an indication of the subject, object or research task;
Research methods - description of the approaches, methods and sources used;
Results are the main data obtained, identified patterns and provisions;
Conclusions and practical significance - interpretation of the results, areas of their possible application and scientific value.

The following is not allowed in the annotation:

general and declarative formulations that do not contain specific information (“a current problem is being considered”, “research has been conducted”, etc.);
verbatim repetition of the article title;
references, footnotes and quotations;
undeciphered abbreviations and acronyms;
descriptions of the author's intentions ("the article will consider", "it is planned to show").

The abstract should present the results already obtained and be formulated in the present or past tense.

Examples of annotations

Example 1 (161 words)

Synthesis and cytotoxic activity of N-alkylated derivatives of berberine against tumor cell lines MCF-7 and A549

The search for new antitumor compounds among derivatives of natural alkaloids remains a relevant area of medicinal chemistry due to the high biological activity and structural diversity of this class of substances. Berberine derivatives are of particular interest due to their confirmed cytotoxic activity against a number of tumor lines; however, their mechanisms of action and structure-activity relationships have been insufficiently studied. The aim of this study was to synthesize new N-alkylated berberine derivatives and evaluate their cytotoxic activity against MCF-7 breast adenocarcinoma and A549 non-small cell lung cancer cell lines. The target compounds were synthesized by alkylation of berberine with chlorobenzyl and its para-substituted analogs in acetonitrile in the presence of potassium carbonate. The structures of the obtained compounds were confirmed by NMR spectroscopy and high-resolution mass spectrometry. Cytotoxic activity was determined by the MTT method after 72 hours of incubation. Eight new compounds were synthesized, with IC₅₀ values for MCF-7 ranging from 1.2 to 6.8 μmol/L. The para-fluorobenzyl derivative was found to be the most active (IC₅₀ = 1.2 μmol/L), 4.3 times higher than the activity of the parent compound. Molecular docking showed that the compound interacts with DNA topoisomerase II, the putative molecular target. These data support the potential for further structural optimization of this class of compounds.

Example 2 (151 words)

VOLTAMMETRIC DETERMINATION OF LEAD, CADMIUM AND COPPER IONS IN NATURAL WATERS USING A MODIFIED CARBON ELECTRODE

Currently, the determination of trace amounts of heavy metals in environmental samples is an important analytical task due to their toxicity and bioaccumulation potential. Existing standard methods of atomic absorption spectroscopy require expensive equipment and complex sample preparation, which limits their application in field monitoring conditions. The aim of this work was to develop and metrologically validate a method for the voltammetric determination of lead, cadmium, and copper ions in natural water samples using a modified carbon electrode. The modification material was Nafion-stabilized bismuth oxide nanoparticles applied to the surface of a glassy carbon electrode by droplet evaporation. The analytical characteristics of the method were evaluated in accordance with the requirements of GOST R ISO 5725. The linear range of determination was 0.5–50 μg/L for all three metals; The detection limits were 0.15 μg/L for lead, 0.08 μg/L for cadmium, and 0.12 μg/L for copper. The relative standard deviation did not exceed 4.2%. The method was tested on river water samples, and the results are comparable to atomic absorption spectroscopy data. The developed method is recommended for rapid monitoring of heavy metals in natural waters.

Example 3 (163 words)

ACCUMULATION OF MICROPLASTICS IN FRESHWATER ECOSYSTEMS OF THE OKA RIVER BASIN AND ITS IMPACT ON THE HISTOMORPHOLOGY OF UNIO PICTORUM

Microplastics are one of the most common modern pollutants of aquatic ecosystems, exerting toxic effects on aquatic organisms and potentially posing a health hazard to humans. The accumulation and biological effects of microplastics in Russian freshwater ecosystems remain understudied, despite the significant environmental risk. The aim of this study was to assess microplastic levels in water, bottom sediments, and tissues of the bivalve mollusk Unio pictorum in the Oka River basin and analyze their impact on the histomorphological parameters of the hepatopancreas. Water and bottom sediment samples were collected at 12 monitoring sites in the spring and summer of 2023. Microplastic particles were identified using mu-IR spectroscopy. Histological sections of the hepatopancreas were stained with hematoxylin and eosin and using the Mallory staining method. The average microplastic concentration in water was 4.7 particles/L, while in bottom sediments it was 312 particles/kg dry weight. Dystrophic changes in the epithelium of the digestive tract and hemocyte infiltration were detected in the tissues of mollusks from highly contaminated sites. Correlation analysis revealed a significant relationship between the concentration of microplastics in bottom sediments and the degree of histological damage (r=0.74, p<0.01). These data demonstrate the real ecotoxicological impact of microplastics on freshwater invertebrates in the studied basin.