FISA (Fully Integrated Wearable Sensor Arrays) for multiplexed perspiration analysis is designed for multiplexed in situ perspiration analysis, which simultaneously and selectively measures sweat metabolites (such as glucose and lactate) and electrolytes (such as sodium and potassium ions), as well as the skin temperature (to calibrate the response of the sensors).The panel of target analytes and skin temperature are selected to facilitate an understanding of an individual’s physiological state. The device contains five skin-conforming plastic-based sensors and commercially available integrated-circuit components (more than 10 chips). The signal-conditioning path for each sensor is implemented with analogue circuits and in relation to the corresponding transduced signal. The circuits are configured to ensure that the final analogue output of each path is finely resolved while staying within the input voltage range of the analogue-to-digital converter. The microcontroller’s computational and serial communication capabilities are used to calibrate, compensate and relay the conditioned signals to an on-board wireless transceiver.