Wearable cellulose textile matrix self-powered biosensor sensing lactate in human sweat

Herein, a self-powered lactate biosensor (SPLBs) was assembled to detect lactate in sweat based on flexible textile matrix enzymatic electrodes. A porous three-dimensional electrode with high flexibility and electrical conductivity was obtained by decorating composites of reduced graphene oxide and carboxylate multiwalled carbon nanotubes onto a cellulose fabric substrate. The excellent enzyme embedding method using a gel electrolyte showed a Michaelis–Menten constant of 1.46 mM, indicating the high enzymatic activity of lactate dehydrogenase. Moreover, the assembled (SPLBs) displayed a sensitivity of 3.16 µW mM −1  cm −2 with a linear range of 0–10 mM and a detection limit of 9.49 µM. Additionally, the biosensor has good tensile flexural stability, selectivity, and long-term stability. When integrated into clothing, the (SPLBs) recovered 91.5–102.3% of lactate from real sweat, with a relative standard deviation of less than 4.16%. This biosensor is promising for sensing lactate in human sweat. Graphical abstract