Modern designs of electrochemical sensor for accurate drug analysis in pharmaceutical and biological samples: Principles, nanofabrication, and key challenges

This comprehensive review discusses the recent advancements in electrochemical sensors tailored for precise drug analysis in pharmaceutical and biological samples. It extensively covers various electrochemical sensing techniques, including voltammetry, amperometry, impedance spectroscopy, and potentiometry. The review also discusses electrode nanofabrication methods such as screen printing, electrodeposition, vapor deposition, sol-gel processes, inkjet printing, 3D printing, and lithography, as well as diverse approaches for modifying electrode surfaces, like self-assembled monolayers, drop-casting, and molecular imprinting. Notably, the review spotlights innovations involving nanoparticles and nanostructured materials, such as metal nanoparticles, metal oxides, quantum dots, carbon nanomaterials, and hydrogels, which aim to enhance sensor performance. The latest research provides critical performance metrics, such as sensitivity, selectivity, limit of detection, and linear dynamic range, offering insights into the evolving capabilities of these sensors. Furthermore, the article highlights groundbreaking sensor designs, including wearable devices, smartphone-compatible sensors, and disposable paper-based sensors. In essence, this all-encompassing review aims to inspire ongoing research and the development of cutting-edge electrochemical sensors, ultimately advancing the field to enable precise drug analysis in both clinical and research settings.