Meat and meat products are one of the key elements of nutrition worldwide. At the same time, food adulteration is a serious problem for both medical and religious reasons. To determine the species composition of meat products and measure the content of impurities, nucleic acid analysis methods are used, which require application of reference materials. The approval in 2024 of the State primary standard for the DNA sequence copies number GET 220–2024 made it possible to begin development of reference materials certified for the species-specific DNA sequences copy number ratio. Reference materials representing solutions of mixtures of genomic DNA isolated from pork, chicken, and cattle were prepared and certified. Based on the trials conducted, at the end of 2024, the types of RM for chicken DNA composition in a cattle DNA matrix (GSO 12743-2024 DNA-Gallus-VNIIM set) and RM for pig DNA composition in a cattle DNA matrix (GSO 12744-2024 DNA-Sus-VNIIM set) were approved at the end of 2024. These reference materials of species-specific DNA content replace existing foreign-made RM analogues and ensure the metrological traceability of measurements performed in the Russian Federation in the food industry to the state primary standard GET 220.

Synthetic sweeteners have found widespread application in the national economy, but their use has some limitations. Safe intake levels for aspartame and acesulfame potassium are established by the recommendations of the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Compliance with safety requirements can be ensured by controlling the content of sweeteners in food products.

In Russia, measurements performed in accordance with GOST standards and certified methods, for which reference materials are essential. The presented research was conducted with the aim of replacing foreign reference materials with domestically produced reference materials to ensure measurement uniformity for the purpose of Russia’s technological sovereignty.

The publication contains information on the development of new types of reference materials for the composition of the synthetic sweeteners aspartame and acesulfame potassium, which are metrologically traceable to the State Primary Standard of units of mass (molar) fraction and mass (molar) concentration of organic components in liquid and solid substances and materials based on liquid and gas chromatography-mass spectrometry with isotope dilution and gravimetry GET 208–2024. Identification of the main component in the reference material was performed using high-resolution mass spectrometry. Characterization of the reference materials was carried out using the mass balance method. The content of related compound impurities was measured using high-performance liquid chromatography with a diode-array UV detector; the content of volatile organic compound impurities was measured using gas chromatography with a flame ionization detector; water content was determined by Karl Fischer coulometric titration. The content of non-volatile impurities was measured by gravimetry for aspartame and microwave plasma atomic emission spectrometry for acesulfame potassium. The homogeneity and long-term stability of the reference materials were studied.

The metrological characteristics of the new domestically produced reference materials demonstrate parity with foreign analogues: the mass fraction of the main component in the pure aspartame is (96.2 ± 0.3)%; the mass fraction of the main component in the pure acesulfame potassium is (99.98 ± 0.01)%.

To obtain reliable measurement results for the content of components in various materials, reference materials with certified content of the studied component are required. Elemental bromine, being a volatile and toxic liquid, is unsuitable as a source material for the preparation of a reference material for the chemical element bromine. The most optimal choice for the reference material is a bromine salt – potassium bromide.

The aim of the study is to develop a certified reference material for composition of potassium bromide based on the same high-purity salt with the certified characteristic «mass fraction of potassium bromide». The mass fraction of the main component in potassium bromide was measured using two methods: a direct method employing coulometric titration with corrections for interfering impurities determined by ion chromatography, and an indirect method based on the scheme of 100% minus the sum of impurities, taking into account their ionic forms.

It is shown that the direct and indirect methods for determining the mass fraction of potassium bromide yield consistent results: (99.871 ± 0.029) and (99.873 ± 0.017)%, respectively. Studies of homogeneity, as well as short-term and long-term stability, were conducted using the coulometric titration. A reference material for potassium bromide composition, GSO 12300-2023, was developed with an interval of certified values of the mass fraction of potassium bromide (99.5–100)% and an expanded uncertainty of the certified value of 0.05% at k=2. The certified value and expanded uncertainty of the mass fraction of potassium bromide for a batch of the reference material were (99.87 ± 0.05)%.

A distinctive feature of the indirect method for determining the mass fraction of potassium bromide implemented in this work is the construction of a chemical composition model of the analyzed object. This model is based on both a priori and experimental data and utilizes two fundamental principles when summing impurity contents: the condition of material (mass) balance and the principle of electroneutrality. The described indirect method is sufficiently universal. For high-purity salts, it enables achieving a relative expanded uncertainty (at k=2) of less than 0.02%. This method can be adopted in analytical practice for assessing the purity of other metal salts where high accuracy is required.

The developed certified reference material can be used to ensure the metrological traceability of measurement results in both titrimetry (precipitation titration) and elemental analysis. It can also be utilized for the preparation or control of certified values for reference materials of bromide ion solution composition, including those in multicomponent mixtures with other anions.

The research presented in the article is aimed at developing reference materials (hereinafter referred to as RMs) for the isotopic composition of ethanol required for measurements in accordance with the requirements of Russian standards and Technical Regulations of the Customs Union. The relevance is due to the expansion of the scope of isotope analysis in various fields, including the food industry, environmental monitoring and customs control. Current reference materials have a limited range of certified values and are not available in Russia due to the imposition of sanctions by unfriendly countries, which creates the need to develop domestic analogues.

The purpose of the research is to create and subsequently certify the metrological characteristics of reference materials for the isotopic composition of ethanol obtained from various raw materials: corn, wheat, sugar beet and synthetic ethanol. For this purpose, a method for preparing reference materials was developed, a pilot batch was produced, tests for homogeneity, long-term and short-term stability were performed, and certified values of the isotopic composition of carbon, oxygen and hydrogen were determined.

The main methods of RM production and certification included isotope mass spectrometry using the Isoprime precisION isotope mass spectrometer (hereinafter referred to as IMS), automated packaging and sealing of ampoules with reference materials. The study of metrological characteristics showed high homogeneity and stability of the developed reference materials, which confirms their suitability for metrological purposes. The certified values of the developed reference materials are consistent with known literature data on the isotopic composition of plant-based ethanol (corn and wheat), which confirms the reliability of isotopic analysis methods and their applicability for identifying biological sources of alcohol. The novelty of the research work lies in the development of domestic reference materials with a wider range of certified values of the isotopic composition of carbon, oxygen and hydrogen compared to analogues, which extends the capabilities of accurate measurements and control in various industries.

The practical significance of the research is the development of new reference materials for quality control of alcoholic products, customs control and state control in the alcohol market. The developed reference materials provide accurate determination of the origin of ethanol, which is especially important for the identification of biological and synthetic sources.

The research results create opportunities for developing reference materials of other substances, such as calcium carbonate, polyethylene and carbon monoxide.

Specific electrical conductivity is one of the most important indicators of water quality in technological processes of microelectronics production, pharmaceutics, thermal and nuclear power engineering; the indicator studied during environmental monitoring. Based on accurate data on specific electrical conductivity of liquid, it is possible to reliably assess the state of production systems and technological processes.

The article describes a study conducted to develop and produce two types of reference materials of specific electrical conductivity of liquid – SEC‑10 (GSO 12746-2024) and SEC‑20 (GSO 12374-2023). The article presents the materials and instruments used in the production of reference materials. An assessment of the relative uncertainty of certified values of long-term and short-term stability is given, calculations of the relative expanded uncertainty of certified values of reference materials are presented in accordance with GOST ISO Guide 35–2015. In the course of the work, the metrological traceability of the certified values of reference materials to the measurements unit of “specific electrical conductivity” reproduced by State Primary Standard of the unit of specific electrical conductivity of liquids in the range from 0,001 to 50 S/m GET 132‑2018 was established.

The developed reference materials were added to the list of available domestic reference materials due to the increased range of specific electrical conductivity values, which is from 1 to 20 S/m. Market availability will allow new reference materials to replace imported analogues, thereby reducing the time and cost of metrological work. The article is addressed to state metrology centers performing verification, calibration and testing for approval of the type of conductometric analyzers. The publication may be useful for organizations conducting scientific research and metrology services of enterprises of various industries.

Video measuring systems are characterized by high accuracy due to their high degree of automation, which allows them to effectively solve production and business tasks. For their calibration and metrological verification, line standards of length are used as material measures reproducing a measurement unit of length. Line standards of length are employed as working standards in various fields of science and technology. However, the continuous development of the regulatory framework and technical standards requires timely updataing of dataa and approaches used in the process of metrological support for line standards of length. The aim of the review is to assess the current state of the regulatory and technical framework used in the Russia for the metrological support of line standards of length. It analyzes the methodological approaches employed for the verification and calibration of line standards of length in accordance with the current State Verification Schedule and outlines potential ways for their further improvement.

Based on the analysis of legislative and regulatory acts, a review of scientific literature, as well as the authors’ own professional experience, factors hindering the development of the metrological support system for line standards of length have been identified. Firstly, the regulatory and technical framework is characterized by a high degree of wear and requires comprehensive modernization. The implementation of modern technologies, such as laser interferometers, will enhance the accuracy and speed of measurements, which is critically important for ensuring the required measurement accuracy and work productivity.

Secondly, it has been established that the application of digital information processing methods, in particular artificial intelligence and machine vision technologies (for example, CCD cameras – cameras equipped with a charge-coupled device as an image sensor) is a promising direction for automating the measurement process and reducing the influence of the human factor. Consequently, the transfer of the measurement unit of length from line standards of length using the comparison method can be adapted to modern realities through an automated reading system. However, this requires solving the problem of the lack of production of line standards of length longer than 1 mm and updataing the technical inventory of existing working standards of the 1st, 2nd, 3rd, and 4th grades.

Thus, the analysis of the current state of metrological support for line standards of length presented in the article convincingly substantiates the urgent need to develop and create a modern installation for verification of line standards of length that meets the requirements for secondary standards of the measurement unit of length. This will ensure high accuracy and reliability of measurements for precision guidance: length gauges – for measuring internal and external dimensions; comparators – for the verification of lower-grade line standards, and also enhance the competitiveness of domestic products on the international market.

Business entities across nearly all economic sectors use continuous weighing batchers and conveyor scales as mass measuring instruments. The accuracy of these instruments directly depends on metrological traceability. However, many enterprises are unable to perform verification of these measuring instruments due to the complexity of the procedure in real production conditions. Consequently, there is a need to improve approaches for transferring a unit of mass to conveyor scales and continuous weighing batchers.

The purpose of this review is to analyze the primary methods for transferring the unit of mass to these measuring instruments, examine their advantages and disadvantages, and describe how various conditions influence measurement accuracy.

The author analyzed data from the Verification module of the Arshin subsystem, which is part of the Federal Information Fund for Ensuring the Uniformity of Measurements (FGIS Arshin of the FIF UEM) for the period 2020–2024. The analysis revealed a growing trend in the use of conveyor belt scales as accounting measuring instruments, despite the complexity of the verification procedure. This trend confirms the critical importance of metrological assurance for the operational reliability and accuracy of these devices.

The study focuses on six calibration and verification methods for conveyor scales and continuous weighing batchers. In particular, a method in which the author has professional involvement is considered – the method based on the use of a 5th-class mass standard. As a result, its advantages compared to other methods have been identified: a) it can be applied to any conveyor scales and batchers; b) it is significantly simpler than pouring; c) it accounts for all the established influencing factors; d) it ensures reliability with traceability to the State Primary Standard for the unit of mass GET 3–2008.

Furthermore, some limitations have been identified, the elimination of which is necessary for further improvement of the approach. Specifically, the method is currently applicable only to conveyor scales and batchers with a relative error of 1% or greater. The conclusions of the review can provide metrologists with a basis for selecting the most optimal calibration and verification methods for batchers and conveyor scales, which constitutes the practical significance of the study. The scientific significance lies in the formulation of proposals for improving the quality and reliability of measurements and expanding the application of continuous weighing batchers and conveyor scales.

Introduction. Acrolein is one of the most widespread toxicants. Under conditions of chronic intoxication, it has a general irritant, allergenic, mutagenic, carcinogenic, embryotoxic effect on the human body. Acrolein can be found in alcoholic beverages, some food products, including fats and frying oils. A review of scientific literature revealed significant knowledge gaps about the acrolein content in grain and fruit distillates, which is explained by the insufficient development of reliable analytical methods for its determination. The content of acrolein in grain and fruit distillates is not regulated by regulatory documents, which served as a prerequisite for conducting this study.

Objective of the study. To develop an express method for the qualitative and quantitative determination of acrolein in grain and fruit distillates using the gas chromatography method.

Objects and methods of the study. The objects of the study were model and calibration solutions of acrolein of 20 samples of fruit and grain distillates. Analytical studies were performed on a gas chromatograph Agilent 6850 with flame ionization detection. ChemStation A.10.02 software was used to process the measurements.

Results and discussion. In the study, optimal chromatography modes were selected that ensure express determination of acrolein content in the mass concentration range of 0.3–10 mg/dm3 in grain and fruit distillates without preliminary sample preparation in 4–5 min. The stability of the „retention time“ and „peak area“ parameters for acrolein was established. It was experimentally confirmed that the calibration graph for acrolein has a linear dependence in the mass concentration range of 0.3–10 mg/dm3 . A correlation dependence between the sample concentration and the detector response was found, the correlation coefficient R2 is not less than 0.99. As a result of studies, a method for the qualitative and quantitative determination of acrolein in grain and fruit distillates was developed. The limits of relative error of the developed method with a confidence of P = 0.95 in the range of mass concentrations from 0.3 to 10 mg/dm3 are less than 28 %.

Conclusions. A new methodological approach to determining acrolein in grain and fruit distillates based on the gas chromatography method is proposed. The conducted research is the basis for the development of a metrologically certified method for the qualitative and quantitative determination of acrolein in alcoholic beverages and the development of reference materials to improve the measurement accuracy. The development of this research area will provide new experimental data on the chemical composition of alcoholic beverages and will improve the quality and safety of alcoholic beverages.