A Tetraphenylethene-Based Rhodamine Hydrazone Chemosensor for Colorimetric and Reversible Detection of Cu2+

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.

The crystal structure of (E)-3′,6′-bis(diethylamino)-2-((5-(diethylamino)-2-hydroxybenzylidene)amino)spiro[isoindoline-1,9′-xanthen]-3-one, C39H45N5O3

C33H31BrN4O3, monoclinic, P21/n (no. 14), a = 11.8558(12) Å, b = 12.1159(11) Å, c = 24.014(2) Å, β = 94.812(2)°, V = 3437.3(6) Å3, Z = 4, Rgt (F) = 0.0574, wRref (F 2) = 0.1725, T = 296(2) K.

The crystal structure of (E)-2-((5-bromo-2-hydroxybenzylidene)amino)-3′,6′-bis(ethylamino)-2′, 7′-dimethylspiro[isoindoline-1,9′-xanthen]-3-one, C33H31BrN4O3

C33H31BrN4O3, monoclinic, P21/c (no. 14), a = 9.3451(7) Å, b = 17.3057(13) Å, c = 18.4402(13) Å, β = 98.4470(10)°, V = 2949.9(4) Å3, Z = 4, R gt (F) = 0.0409, wR ref (F 2) = 0.1106, T = 296(2) K.

Synthesis of Dansyl Cyclen and Preliminary Study of Its Fluorescent Properties

The synthesis of a dansyl cyclen-based compound as a potential chemical sensor has been carried out. The initial study of its fluorescent properties has also been conducted. This study aims to synthesize a cyclen-based compound comprising three identical pendant arms and another different arm carrying a dansyl fluorophore. Producing these heterogenous pendant arms, a-three pendant arm cyclen 9 was reacted with dansyl aziridine 10. The synthesis products were characterized using 1H NMR, 13C NMR, IR, and elemental analysis. In addition, a Fluorescent Spectrophotometer has been used to assess the fluorescent intensity changes of the synthetic ligand in a range of pH 2–13 and when it was titrated with some metal ions. Based on the results of characterization with 13C NMR for compound 2 and additional characterization with IR and elemental analysis for its hydrochloric form 11, it is wisely said that the proposed compound has been successfully synthesized, giving 66% yield as viscous brown oil 2. Moreover, the fluorescent property showed that the higher the pH employed, the higher the fluorescent intensity observed. Meanwhile, the addition of some cationic metals revealed that cadmium (II) gave the highest increase in the fluorescent intensities among other cationic metals.

A novel cholesterol conjugated fluorescence probe for Cu2+ detection and bioimaging in living cells

A cholesterol conjugated fluorescence probe T was designed and synthesized. The probe T can be used for recognition of Cu²⁺ by the absorption spectrum, fluorescence spectrum, and naked eyes respectively in aqueous solution. The cell imaging experiments showed that the probe has good membrane permeability and a huge potentiality for the detection of Cu²⁺ in living cells.

Modulating aggregation-induced emission via a non-conjugated linkage of fluorophores to tetraphenylethenes

A fluorophore (DNS or NBD) is attached to tetraphenylethene via a non-conjugated bridge, endowing the resulting aggregates with distinct emission properties.