A sensitive tetraphenylethene-based fluorescent probe for Zn 2+ ion involving ESIPT and CHEF processes

Synthesis of Bis-tetraphenylethene as a Novel Turn-On Selective Zinc Sensor

The main purpose of this study is the synthesis of novel fluorescent Bis-TPE and the investigation of its wide range of photochemical behaviors. For this purpose, initially, Bis-TPE was synthesized. Following this, the interactions of Bis-TPE with a wide range of ions were studied in EtOH using ultraviolet-visible (UV-vis) and fluorescence spectroscopy. As a result of all UV-vis and fluorescence studies, it was determined that Bis-TPE showed turn-on sensor features against Zn²⁺ ions. Moreover, the limit of detection (LOD) and K_a values of Bis-TPE/Zn²⁺ were calculated as 0.97 μM (970 nM) and 3.76 × 10⁵ M^-1, respectively. Moreover, all reversal studies resulted in switchable on/off variation of the alternative addition of ZnCl₂ and [Bu₄N]OH to Bis-TPE. This result also implies that the probe Bis-TPE also exhibits specific OH^- sensor properties in the presence of zinc.

Novel Quinoline-Derived Chemosensors: Synthesis, Anion Recognition, Spectroscopic and Computational Study

Fluorescent-small molecules offer an excellent source of chemosensors when optimized for detection of anions with sensitivity and selectivity, low-cost and robust synthesis. In the present study we synthesized new quinoline-based...

Ethyl 1-Butyl-2-(2-hydroxy-4-methoxyphenyl)-1H-benzo[d]imidazole-5-carboxylate

Ethyl 4-(butylamino)-3-nitrobenzoate upon “one-pot” nitro-reductive cyclization using sodium dithionite and substituted aldehyde in dimethyl sulphoxide affords ethyl 1-butyl-2-(2-hydroxy-4-methoxyphenyl)-1H-benzo[d]imidazole-5-carboxylate in an 87% yield. The structural characterization was determined by Fourier-transfer infrared spectroscopy (FT-IR), Proton nuclear magnetic resonance (1H-NMR), Carbon-13 nuclear magnetic resonance (13C-NMR), mass spectrometry, Ultraviolet-visible(UV-Vis), photoluminescence (PL), thin-film solid emission spectra, cyclic voltammetry (CV) and thermogravimetric (TGA) analysis. Molecular electrostatic potential (MEP) was studied to determine the reactive sites of the molecule.

A novel switch on and reversible optical sensor as an efficient, selective receptor for Zn(II) ion and its biological application

In the present study, a promising optical sensor (TR) was designed, synthesized, characterized and its chemosensing mechanism has been explored through ¹H NMR, ESI-MS, UV-Vis absorption and emission spectral studies. This compound exhibits a drastic change in its optical properties when treated with Zn²⁺, whereas other metal ions do not respond. This provides a naked eye detection for Zn²⁺ ion. In methanolic medium, Zn²⁺ ion induces strong fluorescence in TR with large Stokes shifts up to ∼132 nm. A 5-fold increase in fluorescence intensity of TR in presence Zn²⁺ ion is due to inhibition of ESIPT (Excited State Intramolecular Proton Transfer) and -C=N isomerization with large increase in the ICT (Intramolecular Charge Transfer) character of TR in the excited state. The Job's plot and BH plots reveal the formation of 1: 1 stoichiometry with an estimated binding constant of 3.9 × 10⁷ M^-1. The detection limit of TR was found to be 3.85 nM. The TR could be regenerated by adding EDTA solution to the complex formed during interaction. The pH studies indicate that TR could render pH dependent fluorescence measurements in a live physiological environment. Computational technique was used to optimize the structures and the theoretical results are correlated with the experimental results. The possible utilization of TR as bio-imaging fluorescent sensor with 98.57% cell viability to detect Zn²⁺ in HeLa cells was also explored by fluorescent cell imager.

A dual functional fluorescent sensor for the detection of Al3+ and Zn2+ in different solvents

A new fluorescent sensor, X, was designed and synthesized based on imidazo[2,1-b]thiazole and 2-hydroxy-1-naphthaldehyde, which could be used to detect Al³⁺ in methanol buffer solution and detect Zn²⁺ in ethanol buffer solution, respectively.

Crystal structure of pyrene-2-carbaldehyde, C17H10O

C17H10O, monoclinic, P21/c (no. 14), a = 8.1312(16) Å, b = 7.8252(16) Å, c = 17.231(3) Å, β = 92.47(3)°, V = 1095.3(4) Å3, Z = 4, R gt(F) = 0.0517, wR ref(F 2) = 0.1281, T = 293(2) K.

Synthesis, crystal structure and aggregation-induced emission of a new pyrene-based compound, 3,3-diphenyl-2-[4-(pyren-1-yl)phen-yl]acrylo-nitrile

The title organic compound, C37H23N, crystallizing in the triclinic space group P [Formula: see text], has been designed, synthesized and characterized by single-crystal X-ray diffaction, MS, NMR and elemental analysis. There are alternating relatively strong and weak intermolecular π-π interactions between adjacent pyrene ring systems, forming a one-dimensional supramolecular structure. The compound is weakly fluorescent in THF solution, but it is highly emissive in the condensed phase, revealing distinct aggregation-induced emission (AIE) characteristics.

A highly sensitive fluorescent probe for bioimaging zinc ion in living cells and zebrafish models

A simple OFF–ON fluorescent probe was prepared and successfully applied for bioimaging Zn²⁺ in living systems.