Calibration-Free Electrochemical Biosensors Supporting Accurate Molecular Measurements Directly in Undiluted Whole Blood

• DOI: 10.1021/jacs.7b05412
• Publication Date: 2017-07-16T18:10:56Z
• Authors: Hui Li; Philippe Dauphin-...; Gabriel Ortega; Kevin W. Plaxco
• Keywords: Square wave; SIGNAL (programming language); Electrochemical gas sensor; Accuracy and precision

The need to calibrate correct for sensor-to-sensor fabrication variation and sensor drift has proven a significant hurdle in the widespread use of biosensors. To maintain clinically relevant (±20% this application) accuracy, example, commercial continuous glucose monitors require recalibration several times day, decreasing convenience increasing chance user errors. Here, however, we demonstrate "dual-frequency" approach achieving calibration-free operation electrochemical biosensors that generate an output by using square-wave voltammetry monitor binding-induced changes electron transfer kinetics. Specifically, frequency dependence their response produce ratiometric signal, ratio peak currents collected at responsive non- (or low) frequencies, which is largely insensitive variations. Using aptamer-based (E-AB) as our test bed, accurate precise sensors against multiple drugs, accuracy measurement targets within better than 20% across dynamic ranges up 2 orders magnitude without each individual sensor.