Wearable electrochemical biosensor based on molecularly imprinted Ag nanowires for noninvasive monitoring lactate in human sweat

Abstract

We proposed a wearable electrochemical biosensor based on Ag Nanowires (AgNWs) and molecularly imprinted polymers (MIPs) prepared on the screen-printed electrode for the noninvasive monitoring of lactate in the human sweat. The MIPs were prepared by electropolymerization of 3-aminophenulboronic acid (3-APBA) with imprinted lactate molecule on the AgNWs-coated working electrode. The MIPs-AgNWs biosensor revealed high sensitivity and specificity for the detection of lactate from 10−6 M to 0.1 M, with the detection limit of 0.22 μM. Furthermore, the sensors presented high stability and reproducibility with sensitivity recovery of 99.8% ± 1.7% during 7 months storage in a dark plastic box at room temperature. In addition, the flexible electrodes also showed stable electrochemical response after been bended and twisted for 200 times, respectively. Such MIPs-AgNWs biosensor was attached on volunteers’ skin for the noninvasive monitoring of the perspiration lactate in vivo. The wearable electrochemical biosensor provides feasibility in near future for the evaluation of human sweat in the military, sports and biomedical fields.