Ahmed Nuri Kursunlu

A fluorescent “turn on” chemosensor based on Bodipy–anthraquinone for Al(III) ions: synthesis and complexation/spectroscopic studies

A novel triazole-linked Bodipy–anthraquinone compound (Bodipy-A) was easily prepared through one step click chemistry. Bodipy-A displayed a remarkable increase in fluorescence intensity in the presence of trace amounts of Al(III). These changes could be attributed to intramolecular charge transfer (ICT), and Bodipy-A also showed high selectivity over a series of other metal ions in methanol/water (9/1). The results obtained from an absorption spectroscopy titration (Job’s plot) suggested a 2:1 ligand-to-metal complex, which was further demonstrated by FT-IR spectroscopy. The binding constant K of the target complex was then calculated using the Benesi–Hildebrand equation. All fluorescence experiments have shown that the compound Bodipy-A has a good selectivity for Al(III) ions. The results show that this system could be used in semi-aqueous systems.

Bodipy/dipyridylamino-based “turn-on” fluorescent chemosensor for trivalent chromium cations: characterization and photophysical properties

{{3,5-Bis[4,4-difluoro,8-(2,6-diethyl,1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene)]}}phenyl-N,N-di(pyridin-2-yl)benzamide (Bodipy-DPy) was designed as an efficient fluorescent chemosensor for Cr(III). The structure of Bodipy-DPy was confirmed by UV-vis spectroscopy, fluorometry, melting point analysis, 1H-NMR, 13C-NMR, elemental analysis and ESI-TOF-MS. Its photophysical properties was investigated by absorption, emission and excitation techniques. Based on chelation assisted fluorescence enhancement, a fluorometric method was developed for trace level detection, selectivity and concentration studies of chromium(III) in EtOH–H2O. The fluorescent ligand behaved as a chemosensor for Cr(III) cations and showed a strong red fluorescence upon coordination with Cr(III), whereas almost no fluorescence was observed for the other metal cations studied. The Bodipy-DPy has absorption and emission maxima at 528 nm and 535 nm, respectively. The equilibrium binding constant of Bodipy-DPy with Cr(III) was calculated as 1.17 × 106 from the Stern–Volmer equation.

Complexation properties and synthesis of a novel Schiff base with triphenylene nucleus

We presented the synthesis of a novel Schiff base and its complexation properties with some transition metal ions in this work. For this, the 2,3,4,6,7,10,11 hexahydroxytriphenylene (HHTP) as starting material was synthesized according to known procedure. Moreover, the 2-((2-chloroethylimino)methyl) phenol material was prepared with reaction of salicylaldehyde and 2-chloroethylamine hydrochloride. To give the 2,3,4,6,7,10,11-hexakis(salicyliminoethoxy)triphenylene (HSE-TP) as a novel Schiff base, the HHTP were treated with 2-((2-chloroethylimino)methyl)phenol in acetone media. Complexation properties of this Schiff base were investigated towards Ni(II), Cu(II), Co(II), Zn(II), Pd(II) and Cd(II) as transition metals. The structures of these new compounds (ligand and complexes) were characterized with FT-IR, magnetic susceptibility measurement, thermal methods (TGA), (1)H NMR and elemental analyses.

Adsorptive removal of Co(II), Ni(II), and Cu(II) ions from aqueous media using chemically modified sporopollenin of Lycopodium clavatum as novel biosorbent

AbstractIn this study, sporopollenin of Lycopodium clavatum spores was used for sorption experiments. (E)-4-((2-hydroxyphenylimino) methyl) benzoic acid (HPBA) immobilized sporopollenin (Sp) was employed as a sorbent in sorption of selected heavy metal ions in aqueous solutions. The sorbent material was prepared with sequential treatment of sporopollenin with silanazing compound and HPBA. Experimental conditions for effective sorption of heavy metal ions were optimized with respect to different experimental parameters using the batch method in detail. pHs for maximum sorption of Cu(II) ≡ Ni(II) and Co(II) ions were found in six and five, respectively. Langmuir, Freundlich, and Dubinin–Radushkevich (D–R) isotherm equations were applied to the experimental data. Thermodynamic parameters such as free energy (ΔGo), entropy (ΔSo), and enthalpy (ΔHo) were also calculated from the sorption results and were used to explain the mechanism of the sorption. The results indicated that this sorbent is successfully empl...

The example of calix[4]pyrrole derivative containing Bodipy unit: fluorometric and colorimetric sensor for F- ion.

A novel chemosensor based on calix[4]pyrrole derivative modified by Bodipy unit has been synthesized, and its complexes with various anions were investigated. The results show that the receptors can selectively recognize biologically important fluoride ions. The binding affinity for fluoride ions was investigated by naked-eye color change, absorption, emission, proton nuclear magnetic resonance spectroscopy. The addition of fluoride ions to an acetonitrile solution of chemosensor can result in an obvious color change (brownish yellow color to straw yellow). The stoichiometries between the receptor and fluoride were determined from the molar ratio plots using the UV-visible spectra, which showed evident 1:1. The proton nuclear magnetic resonance spectral data supported the fluoride anion recognition with the disappearance of the amino proton peaks.

Porphyrin–Bodipy combination: synthesis, characterization and antenna effect

This paper described the synthesis of multichromophoric and π-conjugated macromolecules consisting of two equal Bodipy units and one porphyrin unit (free base). Then, a zinc(II) complex of this macromolecule based on Bodipy and porphyrin was prepared by a classical complex reaction. The formation of nitroporphyrin, aminoporphyrin, Bodipy–porphyrin (PB) and Bodipy–metalloporphyrin (Zn–PB) was confirmed by 1H-NMR, 13C-NMR, elemental analysis, UV-vis/fluorescence spectra, melting point and ESI-TOF-MS techniques. Moreover, the photophysical properties of chromophoric groups such as absorption, emission and quantum yields were investigated for the photoinduced energy transfer in three different organic solvents. The result indicated that the emission of Bodipy in the Bodipy–porphyrin combination was significantly quenched with the formation of the free base and zinc(II) complex of porphyrin. Efficient energy transfer from the Bodipy unit to the porphyrins (free base or Zn–chelate) was observed between 88% and 96% due to high π-conjugation. The energy transfer also occurred from Bodipy to porphyrin though the high polarity of acetonitrile.

Novel magnetite nanoparticle based on BODIPY as fluorescent hybrid material for Ag(I) detection in aqueous medium.

This manuscript describes a highly selective and ultra-sensitive detection of Ag(I) in aqueous solution using amine coated magnetite nanoparticles modified boron-dipyrromethene by spectrofluorometer. Fe3O4 nanoparticles were synthesized by co-precipitation of Fe(2+)and Fe(3+)in an ammonia solution. Amine modified Fe3O4 was prepared by using (3-aminopropyl)triethoxysilane as silanization agent. The covalent binding of boron-dipyrromethene to amine modified Fe3O4 was confirmed by means of Fourier Transform infrared spectroscopy, transmission electron microscopy, dynamic light scattering, UV-vis and fluorimeter measurements and obtained nanoparticle-boron dipyrromethene structure. The binding abilities of nanoparticle-boron dipyrromethene towards different metal ions have been investigated by some spectroscopic methods as UV-vis, fluorescence spectroscopy, Job plot, etc. and the novel surface displayed high selectivity and sensitivity for Ag(I) among all tested metals.

Cu (II) Chemosensor Based on a Fluorogenic Bodipy-Salophen Combination: Sensitivity and Selectivity Studies

A new fluorescent chemosensor (Bodipy-S) derived from Bodipy and Salophen was developed. After the characterization of all compounds, the behavior of the chemosensor Bodipy-S toward p, d and f block-metal ions was investigated by UV-vis and fluorescence spectroscopy. This chemosensor can selectively detect to Cu (II) in methanol-aqueous solution based on chelation enhanced fluorescence (CHEF) and it almost exhibit to a fluorescence quenching effect with 20-fold. The binding constant of the fluorophore was interpreted by using of the Stern-Volmer method and the complex stoichiometry was defined by using Job’s plot. Moreover, the effect of pH was performed by the fluorescence intensities of Bodipy-S in presence of Cu(II) ions. The chemosensor can be successfully used to the detection of Cu(II) in most areas.

Synthesis and trivalent lanthanide ion complexation studies of new macrocyclic receptors based lactam ionophores

This study is the first report on the design, synthesis and photophysical properties of three new macrocyclic receptors based receptors containing two amide bridges. Their binding properties towards trivalent lanthanide ions such as La3+, Gd3+, Tb3+, Dy3+, Er3+ and Yb3+ were investigated by using spectroscopic techniques. With respect to emission intensity changes upon trivalent lanthanide ion complexation, macrocyclic receptors based lactam ionophores showed higher selectivity towards Yb3+ and/or Er3+ ion over other ions. Presence of proximal two amide groups in macrocyclic lactam receptors having different cavity size were observed to play an important role in exhibiting its lanthanide ion binding.

Facile assembly of Bodipy-based metal ion sensor using click chemistry

In this study, two novel 4,4′-difluoro-4-bora-3a,4a-diaza-s-indacenes (BODIPY)-based metal ion sensors were synthesised using ‘click’ chemistry. The coordination modes and binding constants of the complexes formed with a range of metal ions were calculated. Results indicate that both BODIPY molecules can potentially serve as fluorescent sensors for the studied metal cations. The results also show that the BODIPY-based sensors have more selectivity for Zn (II) ions in the presence of other metal ions.