Stretchable and Flexible Non-Enzymatic Glucose Sensor Based on Poly(ether sulfone)-Derived Laser-Induced Graphene for Wearable Skin Diagnostics

The laser-induced graphene (LIG) has a great potential in electrochemically active electrodes for wearable biosensors. Herein, for the first time, a stretchable and non-enzymatic glucose sensor based on LIG derived from commercial poly(ether sulfone) (PES) membranes is reported. The LIG is in situ transferred onto an elastomer and tightly wrapped by the elastomer in one laser carbonization step. Superior to the conventional casting and demolding transfer process, this method avoids the LIG's morphology distortion and loss. By adjusting the laser settings and the patterns, hierarchically structured electrodes are prepared with greatly increased surface areas for glucose detection. The electrodeposited dendritic gold-nanoparticles act as the catalyst for glucose sensing. The optimized flexible sensor demonstrates a linear range for glucose from 10 mu m to 10.0 mm and a detection limit of 26 mu m. The sensor shows a sensitivity of 0.024 +/- 0.001 mA mm(-1) and selectivity toward other interfering metabolites, as well as excellent performance under mechanical bending (stable performance after 500 bending cycles) and stretchability (resistance unchanged after 1000 cyclic stretching at 20% strain). Due to the simplicity of preparation and extraordinary fidelity, the novel PES-LIG sensor is a promising candidate for the next generation of skin-adherent diagnostic devices and wearable electronics.