A promising method for diabetes early diagnosis via sensitive detection of urine glucose by Fe-Pd/rGO

摘要

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 mu M with a limit of detection (LOD) of 1.76 mu M. 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 H2O2 from glucose oxidation. The electron transfer between Fe-Pd and H(2)O2 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.