Functionalized Fe3O4 Nanoparticles as Glassy Carbon Electrode Modifiers for Heavy Metal Ions Detection—A Mini Review

Over the past few decades, nanoparticles of iron oxide Fe3O4 (magnetite) gained significant attention in both basic studies and many practical applications. Their unique properties such as superparamagnetism, low toxicity, synthesis simplicity, high surface area to volume ratio, simple separation methodology by an external magnetic field, and renewability are the reasons for their successful utilisation in environmental remediation, biomedical, and agricultural applications. Moreover, the magnetite surface modification enables the successful binding of various analytes. In this work, we discuss the usage of core–shell nanoparticles and nanocomposites based on Fe3O4 for the modification of the GC electrode surface. Furthermore, this review focuses on the heavy metal ions electrochemical detection using Fe3O4-based nanoparticles-modified electrodes. Moreover, the most frequently used electrochemical methods, such as differential pulse anodic stripping voltammetry and measurement conditions, including deposition potential, deposition time, and electrolyte selection, are discussed.