A review of ratiometric electrochemical sensors: From design schemes to future prospects

Ratiometric electrochemical sensors are being considered a significant advance in the fields of electroanalysis and are now attracting the attention of many research laboratories. Different from classic electrochemical sensors which typically adopt the absolute value of the signal as the output, ratiometric electrochemical sensors possess dual electrochemical signals and the quantitative measurement of target is based on the ratio of these two signals. The ratiometric signal readout mode provides a built-in correction factor to eliminate the contribution from non-specific interferences. Thus, greater reproducibility, accuracy and sensitivity are obtained, which are critical demands of the classic electrochemical sensor. In this review, we discuss recent advances in ratiometric electrochemical sensors. In addition, we give critical perspectives on the different design schemes, development status and application prospects for ratiometric electrochemical sensors.