Non-enzymatic dopamine detection using iron doped ZIF-8-based electrochemical sensor

Abstract

Dopamine plays a vital function in the central nervous, cardiovascular, and endocrine systems. The precise identification of dopamine is essential for the diagnosis and treatment of different disorders. Electrochemical approaches provide a hopeful substitute for intricate methods such as HPLC and mass spectroscopy. However, the presence of other interference from other substances is a challenge. Modifying the electrode surface or using Zeolitic Imidazolate Framework 8 (ZIF-8) coated with iron can enhance sensitivity and selectivity. Iron-modified ZIF-8 (Fe-ZIF-8) has shown excellent catalytic activity. This study proposes the development of Fe-ZIF-8 for dopamine detection using electrochemical methods. Fe-ZIF-8 displayed sensitive and selective performance, surpassing interfering compounds. A successful synthesis of Fe-ZIF-8 composites with varying iron ratios was achieved, with Fe5-ZIF-8 exhibiting the highest oxidation and reduction peaks. The performance of the Fe5-ZIF-8/GCE sensor was evaluated, demonstrating superior sensing performance in linear range of 0.05–20 μM. The limit of detection (LOD) was determined as 0.035 μM, falling within the concentration of dopamine in human serum. The sensor also exhibited selectivity towards interfering substances, including uric acid, ascorbic acid, and urea. These findings highlight the successful synthesis and promising performance of Fe5-ZIF-8 as a selective sensor material.