Biosensors: Biosensors are analytical devices that combine a biological recognition element with a physical transducer to detect and quantify specific biological or chemical substances. They play a critical role in disease diagnostics, health monitoring, drug development, and personalized medicine. By converting biological responses into measurable signals, biosensors enable real-time, sensitive, and specific detection of biomarkers, pathogens, metabolites, and other analytes of clinical relevance. Our biosensors are designed to be miniaturized, portable, and highly integrated, often incorporating microfluidic platforms, and nanomaterials, facilitating the development of point-of-care diagnostic tools. In particular, electrochemical biosensors were extensively exploited and integrated in the microfluidic device to precisely detect the tumor-derived exosomes from liquid biospies.