Flexible Continuous Sweat Glucose Electrochemical Sensor Based on Ni/Co-MOF@PPSF

Flexible electrochemical sensors based on noninvasive materials can continuously monitor blood glucose levels in sweat, making them ideal for personal diabetes management intelligent devices. It is necessary to construct sweat glucose electrochemical sensors that have the ability to both adjust to human skin and reliably monitor. We first synthesized nickel/cobalt metal-organic framework material (Ni/Co-MOF) nanosheets via a solvent-thermal approach. Then, an oil-based polyurethane (OPU)/polypropylene spun-bonded nonwoven fabric (PPSF) was obtained by coating the surface of PPSF. Silver/silver chloride (Ag/AgCl) paste and conductive carbon (C) paste were printed layer-by-layer on the surface of the OPU/PPSF by screen printing, followed by the immobilization of Ni-Co/MOF nanosheets on the working area using a Nafion solution to form a Ni/Co-MOF@OPU/PPSF flexible glucose sensor for continuous monitoring of glucose in sweat. This Ni/Co-MOF@OPU/PPSF flexible glucose sensor retained the high electrocatalytic activity of Ni/Co-MOF for glucose oxidation and exhibited high sensitivity (159.9 μA/mM·cm²), low limit of detection (LOD) (2 μM), and a wide linearly glucose-monitoring range (10 μM-1 mM). Compared to other nonenzymatic sensors, our Ni/Co-MOF@OPU/PPSF flexible glucose sensor has better immunity than other substances present in sweat. Meanwhile, the Ni/Co-MOF@PPSF flexible glucose sensor not only monitors the glucose in sweat at different body temperatures but also maintains good mechanical flexibility and stable electrochemical properties under bending conditions. It is suggested that our flexible glucose sensor can be used for continuous monitoring of glucose in human sweat. Overall, our glucose sensor can be used for the continuous monitoring of glucose in human sweat.