Multifunctional fluorescent switch based on a 3D Co-CP for selective detection of hypochlorite, nitrofuran antibiotics and acetylacetone

Abstract

The abuse of biological and environmental related materials, such as pharmaceutical antibiotics, volatile organic chemicals and toxic ions has become a topical issue that draws the global attention. Thus, the exploration of effective methods for the rapid recognition of contaminants at low concentrations is critical for curtailing pollution and identifing environmental risks. Previous reports have shown that NH2-functionalized LCPs can serve as effective traps of hypochlorite owing to their rapid chemical reaction with hypochlorite. Herein, we strategically prepared a novel three-dimensional (3D) CP, [Co2(edda)(datrz)(H2O)2]·EtOH (Co-CP), using NH2-decorated triazole ligand 3,5-diamino-1,2,4-triazole (datrz) combined with semirigid tetracarboxylic acid 5,5′-(ethane-1,2-diylbis(oxy)) diisophthalic acid (H4edda). The prepared Co-CP features a pcu topology with point symbol of {412.63}. This material exhibits high structural stability in acidic-basic aqueous solution of broad pH scope (1–11), which is favorable for fluorescence detection in aqueous medium. As expected, the open -NH2 sites within the framework endow this fluorescent CP with remarkable detectability towards hypochlorite in aqueous media. Furthermore, Co-CP also displays satisfactory fluorescence response for sensing nitrofuran antibiotics (NFT and NFZ) and acetylacetone with high sensitivity and selectivity along with great interference immunity. Through exhaustive theories calculations and experimental surveys, the possible mechanisms have also been thoroughly investigated. The CP-based multifunctional fluorescent switch designed in this work expands the application of such materials in biological and environmental related areas.