This paper reports the covalent functionalization of graphene oxide (GO) by a presynthesized metal−organic framework NH 2 -MIL-101(Fe) via ultrasonication of the two components. The formation of Fe−O covalent bonding in the NH 2 -MIL-101(Fe)-GO nanohybrid is clearly evidenced, and the covalent bonding still remains after electrochemical reduction. The morphology and structure of the nanohybrid are characterized via scanning electron microscopy, transmission electron microscopy, UV−vis spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and Raman spectroscopy. The electrode based on electrochemically reduced NH 2 -MIL-101(Fe)-GO shows ultrastable and high-sensitive performance in simultaneous electrochemical sensing of three purine metabolic derivatives (uric acid, xanthine, and hypoxanthine); in particular, no signal fading is seen even after running for 120 times. The covalent bonding within the nanohybrid is obviously the key to maintain such a stability.

Sensitive detection of H2O2 in the nano- to micromolar range is critical for health monitoring and disease diagnosis.Two-dimensional transition metal carbides or/and nitrides (called MXenes, MXs) have excellent potential applications...

A simple and easy-operation electrode modification strategy was proposed using Cu-MOF/GO nanohybrids for physiologists and pathologists for the feasible and reliable simultaneous electrochemical detections of DNA bases, namely guanine and adenine.