Tailoring Sensitivity in Electrochemical Nucleic Acid Hybridization Biosensing: Role of Surface Chemistry and Labeling Strategies

Electrochemical nucleic acid hybridization biosensors have become a mainstay to detect DNA or RNA targets of interest in clinical diagnostics, environmental monitoring and food quality control. Despite the great progress they demonstrated during the last years, there is a constant demand to improve their performance, mainly in terms of sensitivity, simplicity of protocols and easy implementation in routine and decentralized determinations. Within this context, the tremendous possibilities offered by both, a judicious interfacing of the electrode surface, and the use of innovative labeling strategies not requiring nanomaterials or nucleic acid amplification, is discussed critically in this review.