To meet global demand, pesticides play a very important role in the control of pests that damage agricultural products. However, overuse of pesticides threatens ecosystems and human health. In recent years, gas chromatography, liquid chromatography, gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry, capillary chromatography and capillary electrophoresis have been used in the determination of pesticides. Although these methods are highly specific, highly selective and sensitive, the high value of sophisticated laboratory equipment and tools is a complex and time-consuming process. Because of this, electrochemical sensors and biosensor platforms have become good analytical methods for detecting pesticides due to a number of advantages, including ease of detection of system manufacturing processes, high sensitivity and selectivity. This article describes the methods of manufacturing portable electrochemical sensors for detecting pesticide residues in fruits and vegetables on site, that is, the achievements in recent years in the field of cyclic voltammetry, square wave voltammetry, differential pulse voltammetry and electrochemical impedance spectroscopy. In addition, detailed information is provided on the basic mechanism and electrochemical sensitivity of these methods. The development of electrochemical methods and real-time monitoring of smartphone technologies, as well as their integration with detection platforms, are discussed. For readers with a scientific and technological focus, this article will provide additional valuable information for understanding the creation of portable electrochemical devices, rapid detection of pesticides, the role of electrochemical sensitive methods and contributing to their further development.

The development of low-cost and highly sensitive electrochemical sensing platforms for pesticide monitoring has attracted significant attention in recent years. In this study, coke-derived carbon (CDC) was successfully synthesized from petroleum coke through high-temperature carbonization under a nitrogen atmosphere. Subsequently, a CDC@CuO-NP nanocomposite was fabricated by depositing copper oxide nanoparticles onto the CDC matrix. The morphology, structure, and elemental composition of the synthesized materials were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and elemental mapping analyses, confirming the successful formation of the composite and the uniform distribution of CuO nanostructures on the carbon surface. Electrochemical characterization demonstrated that the incorporation of CuO significantly enhanced the electrochemical performance of CDC by increasing the electroactive surface area and facilitating electron transfer. The CDC@CuO-NP-modified glassy carbon electrode was applied for the electrochemical detection of dichlorvos (DDVP) using electrochemical impedance spectroscopy (EIS). The sensor exhibited a concentration-dependent increase in charge-transfer resistance and showed a linear response in the concentration range of 247–3770 nM, with the regression equation y = 47.1458C + 111.8162 and a correlation coefficient of R² = 0.9832. The developed sensor achieved a low limit of detection (LOD) of 2.3 nM, demonstrating high sensitivity toward DDVP. These results indicate that the CDC@CuO-NP nanocomposite is a promising, low-cost, and efficient electrode material for the sensitive determination of organophosphorus pesticides and has considerable potential for environmental monitoring and food safety applications.

Continuous reforms in the field of education, focused on the introduction of innovative technologies, create significant difficulties for higher education institutions in the context of the effective development of students' research competence. This problem is particularly acute in interdisciplinary courses such as physico-chemical analysis methods, where students must not only master complex theoretical concepts, but also develop practical laboratory skills, analytical thinking and the ability to solve real scientific problems independently. The purpose of this study is to bridge the gap between theory and practice in higher education chemistry courses by introducing an integrated educational model aimed at developing students' research skills and learning activities. To solve the tasks set, a new pedagogical strategy has been developed and tested. This strategy describes the combination of a case method with basic project management tools in a mixed learning format. The main objective was to combine theory and practice more effectively and actively involve students in the learning process. The authors used and analyzed mixed methods combining theoretical analysis with quasi-experimental pedagogical intervention to study the effectiveness of an integrated learning model in developing students' research competence in the field of physico-chemical analysis methods. The authors conducted a diagnostic assessment of students' research competence in order to determine the basic levels of motivation. The model is implemented at the undergraduate level in chemistry courses, mainly in the discipline "Physico-chemical methods of analysis". Students worked in small groups with real scientific cases and completed project tasks, including planning experiments and presenting results. Their learning experience and research skills are assessed before and after the implementation of the model through questionnaires, classroom observations, and analysis of project reports. The results show a marked improvement in the ability to formulate research questions, develop experimental plans, and work with data. In addition, students demonstrated a deeper understanding of physico-chemical analysis methods and greater confidence in applying theoretical knowledge in the laboratory.