A water-soluble cationic oligopyrene derivative: Spectroscopic studies and sensing applications

Fluorescent Detection of 2,4‐DNT and 2,4,6‐TNT in Aqueous Media by Using Simple Water‐Soluble Pyrene Derivatives

“…the efficiency of PET between the OPBEAB/SDSp robe and TNT) de- pends strongly on the ratio of reagents and the mixing sequenced ue to the possibility of detachment of TNT molecules from the OPBEAB backbone, as suggested by the authors, and their trapping by the SDS micelle to decrease the quenching constants. [27] Thes ame trend has been observedb yG ho and co-authors for micellar solutions of tweezers-likepyrene derivative in semi-aqueousc onditions. [29] In addition, none of the so far reported probes/sensors demonstrated ah igher response to 2,4-DNTv ersus TNT in aqueous solutions.…”

“…[16a] Am icellar solution of fluorophore is indeed more sensitive to the quenching by NACs than an equivalent concentration of fluorophorei nasimple solvent. [26][27][28][29] Therefore, at the next step, aiming to improve the surface-active properties and impart hydrophilicity,w es ynthesized 6-(pyrene-1-ylsulfonamide)hexanoic acid 5 in 63 %y ield, starting from sodium salt of 6-aminocaproic acid by reactingw ith pyrene-1-sulfonyl chloride in absolute THFi nt he presenceo fB u 4 NBr as ap hase transfer catalyst( Scheme 1). 6-(6-(1-Pyrenesulfamido)hexanamide)hexanoic acid 6 was isolated only in 5% yield, alongw ith product 5 (41 %) and 1-pyrensulfonic acid 3 (15 %) by using the same reactions equence in the presence of ah igher amount( i.e.…”

“…The high value of Stern-Volmer constant (K sv TNT = 5.3 10 5 m À1 )w as attributed to the formation of pseudo-micelles in aqueous solution. [27] Ding and co-authorsu tilized electrostatic interactions between bis-imidazolium tweezers-likep yrene probesa nd charged or neutral organic micelles to prove the determinative role of the type of micelles in adjusting fluorophore distribution in micellar solu-tions, whichi nfluences the sensing behavior towards nitro-explosivesi na queous solutions. [28] Gho andc o-authors reported unprecedentedly high binding constants due to the excimer fluorescencequenching by TNT( K sv TNT = 110 6 m À1 )w hile using micellar solutionso ft weezers-like pyrene derivative in semiaqueous conditions.…”

A novel surfactant-like fluorophore and its probing ability to the aggregation of amphiphilic compounds

“…As it is well known, pyrene is a popular and excellent polarity probe [15,23,24]. The so called and widely used "pyrene scale" is the using of intensity ratio of peak 3 and peak 1 (I 384 /I 373 ) of its emission spectrum, which is largely dependent upon the polarity of its micro-environment.…”

Branched benzothiadiazole-cored oligomers with terminal carbazoles: Synthesis and fluorescence probing nitroaromatics

“…For example, Tao and coworkers have found the fluorescence quenching efficiency of metalloporphyrin was up to 60% after exposed to TNT vapor for 10 s [6]. Chen and coworkers had synthesized a water-soluble cationic oligopyrene, whose K sv (SterneVolmer constant) and detection limit towards TNT reached 5.30 Â 10 5 mol À1 L and 70 ppb in aqueous solution, respectively [7]. Since the fluorescence quenching mechanism of the sensory materials in detecting nitro compounds can be mainly ascribed to the photo-induced electron transfer or the formation of the chargeetransfer complex, the luminescent electron-rich conjugated compounds become good candidates as fluorescent probes for sensing nitroaromatics.…”