Biosensors are common analytical devices, capable of sensing a myriad of
biological analytes, including cancer biomarkers. Although biosensors have different
transducer types, electrochemical biosensors provide fast analysis time, high
sensitivity, and the ability to perform complex measurements such as multiplexed
analysis or screening tests for early diagnosis and prognosis of cancer. This chapter
describes the background and theory of electrochemical sensors and introduces the
main readout techniques. Innovative electrochemical biosensing strategies for analysis
and quantification of important early cancer biomarkers, which include circulating
nucleic acids (e.g., circulating tumour DNA, gene mutations, and microRNA) proteins,
circulating tumour cells, and extracellular vesicles are discussed with the recent
developments to provide an overview of the possible academic and clinical approaches
Keywords: Biosensor, Early Detection, Electrochemistry, Voltammetry, Impedance, Biomarker, Exosomes, microRNA.
