A water-stable copper-based nanosized metal–organic framework for discriminative sensing of amines

Abstract

The ability to design new metal–organic frameworks (MOFs) from different functional groups and different metals can lead to multifunctional materials with a discrimination capacity between chemically similar structures. Furthermore, MOFs produced at the nanoscale (nano-MOFs) appear to be innovative and highly promising materials for the development of improved bioanalytical applications (e.g. chemical sensing). Here, a water-stable green copper-based nano-MOF, [Cu(DHBDC)(H₂O)_2−x(DMF)_x] (1), was prepared at the nanoscale size using polyacrylic acid at 5 °C in order to obtain nanocrystals. The resulting nano-MOF displays an intense fluorescence behaviour, where the presence of strong basic aliphatic amines with a low cone angle leads to “turn-off” of the emission at a rate depending on their nature. This new nanomaterial has proven to be useful as a discriminative sensor of amines either in a vapor phase via colorimetric detection or in water solution via luminescence analysis.