Advances in electrochemical methods for the determination of ephedrine: Current status and future trends

The accurate and reliable detection of ephedrine-type alkaloids has become increasingly critical due to their dual role in legitimate therapeutic applications and potential misuse in illicit drug production. The development of rapid and sensitive detection methods is particularly important for pharmaceutical quality control, anti-doping monitoring in sports, and law enforcement agencies conducting on-site screening, where traditional chromatographic techniques may be impractical due to their complexity and cost. This review examines recent developments in electrochemical methods for ephedrine detection, focusing on advances in electrode materials, surface modification strategies, and analytical methodologies. We discuss the fundamental aspects of ephedrine's electrochemical behavior, including electron transfer mechanisms, pH effects, and mass transport phenomena. Particular attention is given to innovative electrode modifications incorporating nanomaterials, conducting polymers, and molecular recognition elements that have dramatically enhanced detection capabilities. The emergence of novel composite materials, including carbon-metal oxide hybrids and molecularly imprinted polymers, has enabled unprecedented levels of sensitivity and selectivity. We evaluate various analytical approaches, from fundamental voltammetric techniques to sophisticated flow-based systems, highlighting their strengths and limitations. The integration of these methods into practical applications across pharmaceutical quality control, environmental monitoring, food safety, and clinical diagnostics is critically assessed. The review concludes with an examination of current challenges and emerging trends, including the development of portable detection systems and the integration of artificial intelligence for signal processing.