Acoustics-catalyzed e-tongues for high-performance detection and identification of sweat metabolites

The capability for high-precision detection and identification of sweat metabolites is of great importance for personalized healthcare, disease monitoring, and early management of health risks. In this study, we develop an acoustics-catalyzed e-tongue (ACET), which compactly integrates an ultrasonic actuation unit with a biosensor unit based on the oxygen reduction reaction mechanism, enabling substantially enhanced sweat metabolite detection and identification compared with the standalone biosensor unit. Owing to the synergistic effects of ultrasonic excitation and the accompanying acoustofluidic effects, the steady-state response of the biosensor is experimentally improved by up to one order of magnitude (10 × ), while the limit of detection is reduced by as much as 80% through ultrasonic catalysis. Moreover, a unique metabolite identification strategy is proposed for the ACET, achieving a 100% success rate for metabolite-type identification of NaCl and KCl under high-concentration conditions with strong ultrasonic excitation. Beyond its outstanding performance in sweat metabolite detection and identification, which is highly attractive for healthcare management, the ACET provides a robust and versatile platform for physically enhancing electrochemical reactions through ultrasonic catalysis, holding strong potential for a broad range of biosensing applications.