WEARABLE SENSOR

Small, 15, 1901190 (2019)

Wearable multifunctional sweat-based sensingis a promising strategy for noninvasive biomarker monitoring. However, in spite of the progressive improvements through various strategies, sweat-based biosensors still face several challenges, for example, operating instability of enzymes or biomaterials, limited detection range and sensitivity, and poor shelf life of working electrodes.

Recently, Alshareef et al. from King Abdullah University of Science and Technology (KAUST) reported a stretchable, wearable, and multifunctional biosensor based on MXene/Prussian blue (Ti₃C₂T_x/PB) composite. Due to the metallic conductivity and excellent electrochemical activity of Ti₃C₂T_x, the Ti₃C₂T_x/PB composites exhibited distinctly improved electrochemical performance when compared to graphene/PB or carbon nanotubes/PB composites. Furthermore, the implemented solid-liquid-air three-phase interface design ensures a sufficient supply of O₂ and increases the stability of biosensors. As a result, typical electrochemical sensitivities of 35.3 μA mm^–1 cm^–2 for glucose and 11.4 μA mm^–1 cm^–2 for lactate are achieved, together with the high sensitivity and good repeatability during in situ perspiration monitoring of human subjects. This work represents an essential step toward the realization of ultrasensitive enzymatic wearable biosensors for personalized health monitoring.

You Meng and Johnny C Ho (Materials Science and Engineering, City University of Hong Kong, Hong Kong SAR, China)

doi: 10.1088/1674-4926/40/11/110202