Sponge-inspired MXene@CeO2 detector for ultra-sensitive detection of glucose

Abstract

Non-invasive sweat detectors can monitor the glucose level of diabetes in a painless way. However, most detectors need to collect enough sweat through external exercise or active stimulation, which increases the inconvenience of the user and reduces the applicable population. In this study, we propose an ultra-sensitive biomimetic glucose detector to detect the sweat produced by thermoregulation without additional exercise and stimulation. Inspired by the predator process of sponge in the sea, the sensing material of MXene (Ti3C2Tx) @CeO2 hydrogels employed the “laminae-trestle-laminae” (L-T-L) structure of sponge to adsorb and transport glucose molecules in sweat. CeO2 grafted onto the MXene surface can detect glucose by the catalytic activity of CeO2. The glucose detector with an ultra-low limit of detection (LOD = 0.004 μM), excellent sensitivity (801.27 μA⋅μM−1⋅cm−2), and a broad linear detection range (LDR = 0.01–2.5 μM) can satisfy detection requirements in human sweat after dilution. In real applications, the detector can detect glucose in the sweat of diabetic patients for five consecutive days and detect the glucose content in the daily drinks of patients. Our findings demonstrate the high potential of sponge-inspired MXene@CeO2 glucose detector for routine medical testing.