Selective Sensing of Metal Ions and Nitro Explosives by Efficient Switching of Excimer-to-Monomer Emission of an Amphiphilic Pyrene Derivative

Abstract

An amphiphilic pyrene derivative exhibiting unusually stable excimer emission due to strong aggregation is presented. The aggregated system served as an intelligent sensor for metal ions and nitro explosives in aqueous media. The excimer displayed excellent selectivity toward Cu2+ among the tested cations. The observation was interpreted on the basis of chelation of metal ions involving the hydroxyl and amino groups of two molecules, leading to the ligand-to-metal charge-transfer (CT) process. The excimer was further applied for the cell imaging of Cu2+ ions. Also, while treating the excimer with various nitro explosives, it displayed efficient 2,4,6-trinitrophenol sensing, corroborating mainly the CT process from pyrene to the analyte due to intercalation of the analyte within pyrene.

Multireference Approaches for Excited States of Molecules

“…These species are named aromatic excimers and exciplexes (AE's) in the case of identical and non-identical chromophores, respectively. The use of AEs as chemosensors 963 , molecular beacons, 964 and light-harvesting materials 965 The pyrene excimer, the first AE observed experimentally, 967 has become probably the most representative species among all AEs (see e.g., Ref 968 and references therein for the application of the pyrene-based excited state associates). The most important property of pyrene AE is the concentration dependence of its fluorescence spectrum, characterized by a singly redshifted, broad and structureless band.…”

Pyrene-based monomer-excimer dual response organosilicon polymer for the selective detection of 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitrophenol (TNP)

“…Since intermolecular excimers of pyrene were observed in solution, 1 numerous pyrene-based fluorescence probes via the formation or destruction of the excimer have been designed and applied in biology (e.g., nucleic acids, 2 proteins, [3][4][5] bacteria, 6 etc. ), chemistry (e.g., detection of cations, 7,8 anions, 9,10 pH, 11,12 nitro compounds, 13,14 etc. ), and materials (e.g., responsive materials, [15][16][17] optical materials, 18-20 etc.).…”

Quinoline-tagged fluorescent organic probes for sensing of nitro-phenolic compounds and Zn2+ions at the ppb level

“…Several fluorescent materials such as conjugated polymers, [16][17][18] macromolecules, 19 carbon dots, 20,21 small organic probes, [22][23][24][25][26][27][28][29][30][31][32][33] cages, 34,35 covalent organic frameworks [36][37][38][39] and metal-organic frameworks [40][41][42][43][44][45][46][47][48][49][50] have been utilized for TNP and small molecule detection. Most of these demonstrated TNP sensing in dichloromethane (DCM), dimethylformamide (DMF), tetrahydrofuran (THF) and other organic and aqueous-organic solvents, [16][17][18][19][33][34][35][36][37][38][39][40]42,…”

“…Most of these demonstrated TNP sensing in dichloromethane (DCM), dimethylformamide (DMF), tetrahydrofuran (THF) and other organic and aqueous-organic solvents, [16][17][18][19][33][34][35][36][37][38][39][40]42,43 however, for practical usage detection in water is highly in demand. 20,21,[27][28][29][30][31][44][45][46][47][48][49][50][51] Thus, efforts are still required in developing fluorescent materials with high stability in water for this detection purpose. Various analytical techniques such as surface-enhanced Raman spectroscopy, mass spectrometry, gas chromatography, cyclic voltammetry and fluorescence spectroscopy have been employed for TNP detection out of which fluorescence based sensing has gained more attention due to cost-effectiveness, high sensitivity, real-time detection and rapid response time.…”