The versatility of microbial fuel cells as tools for organic matter monitoring.

Water monitoring and remediation require robust, low-cost, and reliable test systems that can couple with prompt treatment interventions. Organic matter (BOD, COD), toxicants, heavy metals, and other pollutants in water need to be regularly inspected. Microbial fuel cells (MFCs) have already gained popularity as BOD biomonitoring systems as these don't need an external transducer or power source. Moreover, these systems are cost-effective, compact, biodegradable, reusable, portable, and applicable for on-site measurements. MFCs truly stands out as online BOD measurement devices as they provide wide detection range (0-25 g/L), low response time (2-4 min) and longer stability in continuous operations (2-5 years) in a cost-effective approach. This review examines the benefits, kinds, performance metrics, and signal optimization of the current state-of-the-art of the BOD measurement, with detailed focus on MFC-based BOD biomonitoring systems. This review covers the important technological breakthroughs in practical applications with associated bottlenecks to develop reliable sensing systems.