Trefoil-Shaped Metal–Organic Cages as Fluorescent Chemosensors for Multiple Detection of Fe³⁺, Cr₂O₇^2–, and Antibiotics

Abstract

The construction of metal–organic cages (MOCs) with specific structures and fluorescence sensing properties is of much importance and challenging. Herein, a novel phenanthroline-based metal–organic cage, [Cd3L3·6MeOH·6H2O] (1), was synthesized by metal-directed assembly of the ligand 3,3′-[(1E,1′E)-(1,10-phenanthroline-2,9-diyl)­bis­(ethene-2,1-diyl)]­dibenzoic acid (H2L) and CdI2 using a solvothermal method. According to single-crystal X-ray analysis, cage 1 exhibits a rare trefoil-shaped structure. Meanwhile, the discrete MOCs are further stacked into a 3D porous supramolecular structure through abundant intermolecular C–H···O interactions. Additionally, through exploration of fluorescence sensing on cations, anions, and antibiotics in aqueous solution, the experimental results indicate that cage 1 has excellent fluorescence sensing abilities for Fe3+, Cr2O7 2–, and nitrofuran and nitroimidazole antibiotics. The sensing ability of 1 remains unaltered for five cycles toward all analytes. The above results suggested that cage 1 can be considered a potential multiple sensor for the detection of Fe3+, Cr2O7 2–, and some antibiotics.

Carbon within carbon: growth of excitation-independent CDs within functional mesoporous carbon towards detection and adsorption of a specific nitrofuran class of antibiotics

“…6,13,14 Among them, optical methods, especially uorescence detection of antibiotics, have garnered attention due to their high sensitivity, user-friendliness, low operational cost, and fast response. [15][16][17][18][19] Similarly, various remediation methods, including chemical degradation, catalytic oxidation, coagulation, membrane ltration, and adsorption, have been studied. [20][21][22][23][24] Among them, adsorption is considered a less expensive and effective method for the remediation process.…”

Responsive macrocyclic and supramolecular structures powered by platinum

“…Metal centers have become an essential component for supramolecular design, as they unlock a whole range of properties that are unrivaled by organic analogues. These include tunable luminescence, 16 redox activity, 17 magnetic susceptibility, 18 anti-aromaticity, 19 catalytic activity, 20 and multi-responsiveness. 21 In recent years, our group has focused on incorporating platinum into small molecules using cyclometalating ligands to elicit responsive behavior.…”

Single-phase white light material and antibiotic detection of lanthanide metal–organic frameworks

“…[29][30][31][32][33] Due to its benefits of simplicity, high efficiency, fast response, and high selectivity, fluorescence sensing has attracted much attention. [34][35][36][37][38] Benefiting from the strong fluorescence emission and stable structure, the fluorescence detection performance of HNU-82 for antibiotics was also investigated. The fluorescence intensity of HNU-82 has a good quenching effect on nitrofurazone (NZF) and nitrofurantoin (NFT) in aqueous solution with the detection limits of NZF and NFT were 6.60 × 10 −7 mol L −1 and 4.62 × 10 −7 mol L −1 , respectively.…”