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

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.