Fig. 1: Schematics of wearable multimodal biochip for assessing exercise metabolic risk and serum correlation through sweat analysis.

a Schematic of the biochip on skin for multimodal sweat sensing and two sources of sweat Phe, including skin surface and blood partitioning. b Indicative negative correlation between sweat Phe concentrations and sweat rates among individuals, along with the calculation method of Phe secretion rate (inlets area of 75.36 mm²) and the division of different metabolic risk areas. c Mechanism of the E-MIP electrode for detecting Phe by direct electrocatalytic oxidation and theoretical simulation of charge transfer between the E-MIP electrode and a Phe molecule under an external electric field. The red arrow represents the direction of the electric field. d Working principle and cross-section of the microfluidic module with vertically assembled structure. e Comparation of Phe DPV responses of the integrated wireless system and pristine electrodes. f Correlation of sweat rates and Phe levels among individuals at the same exercise time point, along with division of different sweat Phe secretion rates. The starred data indicates the subject with the highest secretion rate in this study. Data from 16 healthy subjects. g Correlations of sweat and serum Phe level in two subjects. The dashed lines represent linear-fitted trendlines. h Comparison of recent advances in sweat sensing. **: this work, Tyr tyrosine, BCAAs branched chain amino acids, CRP C-reactive protein, HB β‑hydroxybutyrate, UA uric acid, VC Vitamin C.