Functionalized Microwires-Based Bundle Electrodes for Detection of Multiplexed Metabolites in Interstitial Space

Metabolic substances play a pivotal role in maintaining the body's regular physiological functions. When these processes are disrupted, it can lead to metabolic disorders which may cause severe damage to various organs. Diabetes mellitus, a prevalent metabolic disorder, arises from disturbances in sugar metabolism among other substances. Consequently, there's a pressing need to monitor metabolite levels for early diagnosis. To address this, in this study, a semi-implantable metabolite sensing system developed around functionalized microwires-based bundle electrodes (FMBE) is introduced. This FMBE device tracks glucose, hydrogen peroxide (H 2 O 2 ), and uric acid (UA) levels in vivo in real time, sensitively, and continuously. The FMBE is coated with Au nanoclusters and carbon nanotube–2D carbides and nitride (MXene) nanocomposites to enhance sensing surface area. In vitro characterizations affirm the FMBE's linear responsivity, detection sensitivity, and selectivity toward glucose, H 2 O 2 , and UA sensing. In addition, in in vivo testing in healthy and diabetic rats, it is demonstrated that FMBE is able to continuously monitor interstitial glucose, H 2 O 2 , and UA concentrations after implantation. The FMBE system, thus, stands out as a promising platform for real-time, in situ monitoring of metabolite concentrations, potentially assisting in the diagnosis of diabetes and associated complications.