A promising method for diabetes early diagnosis via sensitive detection of urine glucose by Fe[sbnd]Pd/rGO.

Abstract To develop a highly sensitive colorimetric detection method for the diabetes early diagnosis by determining the glucose in urine instead of blood can avoid the painful blood collection and risks of cross infection. In this paper, novel artificial enzyme mimics were formed by loading bimetallic nanoparticle Fe Pd on the surface of reduced graphene (rGO). Also, we proposed a Fe Pd/rGO coupled with portable paper sensor for the detection of glucose in urine. The results indicated that urine glucose can be sensitively detected in a wide range of 1–200 μM with a limit of detection (LOD) of 1.76 μM. Most important, the color difference along with the increase of urine glucose concentration can be easily distinguished by naked eyes, which is important to its practical usage in screening and diagnosis of diabetes. Furthermore, the reason of the high sensitivity of Fe Pd/rGO towards glucose was investigated in detail via various probing experiments. Fe Pd/rGO has an artificial enzyme mimic activity, which can catalyze O 2 and generate H 2 O 2 from glucose oxidation. The electron transfer between Fe Pd and H 2 O 2 will produce •OH that can oxidize terephthalic acid (TMB) by emitting a blue color. The findings in this study provide a promising alternative for the early screening and diagnosis of diabetes. Graphical abstract Hydrogen peroxide, as the product of glucose oxidation, was adsorbed and catalytic decomposition to form Free radicals (•OH) on the surface of Fe Pd/rGO nanocomposite via the partial electron exchange interaction. The strong oxidation performance of •OH can promote catalytic oxidation of TMB so as to improve sensitivity of glucose detection. Image 1 Highlights • Highly sensitive Fe Pd/rGO nanosensor were formed to detect glucose concentration. • The formation of •OH provide excellent glucose detection performance for Fe Pd/rGO nanosensor. • Sensitive visual detection of urine glucose was realized with portable paper sensor. [ABSTRACT FROM AUTHOR]