Use of dipyridile amine functionalized magnetic nanoparticles for preconcentration and determination of lead ions in food samples.

Novel dipyridile-modified Fe3O4 nanoparticles were synthesized and characterized by infrared spectroscopy, thermal gravimetric and differential thermal analysis, elemental analysis, high-angle X-ray powder diffraction, and scanning electron microscopy. A novel nano-sorbent was used for rapid extraction, preconcentration and determination of trace amounts of lead(II) ions by flame atomic absorption spectrometry. Various adsorption and desorption parameters were optimized during this study.

Experimental design methodology applied to mercury determination: hair samples as a mercury bioindicator.

The application of modified magnetic nanoparticles in extraction of trace Hg was investigated. For this purpose, surfaces of magnetic nanoparticles were modified by 2-picolamine and then utilized as a solid-phase sorbent for Hg(II) extraction. A statistical method, based on surface response design, has been used for the optimization of Hg ion elution from the magnetic nanoparticles.

Sonoelectrochemical synthesis of a new nano lead(II) complex with quinoline-2-carboxylic acid ligand: a precursor to produce pure phase nano-sized lead(II) oxide.

A new lead complex, [Pb(Q)2] (1) (Q=quinoline-2-carboxylic acid), was prepared via conventional electrochemical method in a fast and facile process and fully characterized by (1)H and (13)C NMR, IR, UV spectroscopies and elemental analysis. The nano-structures of same compound were successfully prepared at 25, 48 and 60°C by a facile and environment-friendly sonoelectrochemical route. The new nano-structure particles were characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and elemental analysis.

Novel Cd(II) ion imprinted polymer coated on multiwall carbon nanotubes as a highly selective sorbent for cadmium determination in food samples.

The application of a novel Cd(II) ion imprinted polymer coated on multiwall carbon nanotubes was investigated for preconcentration and determination of low levels of Cd ions. This novel sorbent was characterized by scanning electron microscopy, thermal gravimetric/differential thermal analysis, elemental analysis, and FTIR spectrometry. Effects of various factors, such as pH of the sample solution, eluent (type, concentration, and volume), and flow rates of the sample and eluent, were evaluated in this study.

Novel ion imprinted polymer magnetic mesoporous silica nano-particles for selective separation and determination of lead ions in food samples.

A novel Pb(II) ion imprinted polymer coated on magnetic mesoporous silica was synthesised and characterised by scanning electron microscopy (SEM), thermal gravimetric/differential thermal analysis (TG/DTA), elemental analysis (CHN) and low angle X-ray powder diffraction (XRD). The application of this sorbent was investigated in preconcentration and determination of low concentrations of lead ions. Through this study, various effective factors on determination, such as pH of the sample solution, eluent including type, concentration and volume, adsorption and desorption time which are effective on the method efficiency, were appraised.

Dimethyl-bis-(2-methyl-quinolin-8-olato-κ(2) N,O)tin(IV).

The Sn(IV) cation in the title compound, [Sn(CH3)2(C10H8NO)2], is N,O-chelated by two 2-methyl-quinolin-8-olate anions and coordinated by two methyl groups in a skew-trapezoidal bipyramidal geometry. In the mol-ecule, the two quinoline ring systems are twisted to one another at 10.91 (18)°.

μ-1,2,3,4-Tetra-kis(pyridin-4-yl)butane-κ(2) N (1):N (4)]bis-[trimeth-yl(thio-cyanato-κN)tin(IV).

In the title compound, [Sn2(CH3)6(NCS)2(C24H22N4)], the 1,2,3,4-tetra-kis-(pyridin-4-yl)butane ligand uses the pyridine N atoms at the ends of the butyl chain to coordinate to two trimethylthiocyanatotin(IV) units, forming a dinuclear structure. The Sn(IV) atom in the mol-ecule shows a distorted trans-trigonal-bipyramidal coordination with the methyl groups in equatorial positions. The mol-ecule lies on a center of inversion, with the mid-point of the butyl chain coinciding with this symmetry element.

Di-μ2-isopropano-lato-octa-methyl-bis-(μ-4-methyl-5-sulfanyl-idene-4,5-dihydro-1H-1,2,4-triazol-1-ido-κ(2) N (1):N (2))di-μ3-oxido-tetra-tin(IV).

The tetra-nuclear title compound, [Sn4(CH3)8(C3H7O)2O2(C3H4N3S)2], lies about a center of inversion; the mol-ecule features a three-rung-staircase Sn4O4 core in which two Sn(IV) atoms are bridged by the 4-methyl-5-sulfanyl-idene-4,5-dihydro-1H-1,2,4-triazol-1-ide group. The negatively charged N atom of the group binds to the terminal Sn(IV) atom at a shorter distance [Sn-N = 2.236 (2) Å] compared with the neutral N atom that binds to the central Sn(IV) atom [Sn← N = 2.

Di-μ2-ethano-lato-octa-methyl-bis-(μ-4-methyl-5-sulfanyl-idene-4,5-dihydro-1H-1,2,4-triazol-1-ido-κ(2) N (1):N (2))di-μ3-oxido-tetra-tin(IV).

The tetra-nuclear title compound, [Sn4(CH3)8(C2H5O)2O2(C3H4N3S)2], lies about a center of inversion; the mol-ecule features a three-rung-staircase Sn4O4 core in which two Sn(IV) atoms are bridged by the 4-methyl-5-sulfanyl-idene-4,5-dihydro-1H-1,2,4-triazol-1-ide group. The negatively charged N atom of the group binds to the terminal Sn(IV) atom at a shorter distance [Sn-N = 2.240 (3) Å] compared with the neutral N atom that binds to the central Sn(IV) atom [Sn← N = 2.

Dimeth-yl(1,10-phenanthroline-κ(2) N,N')bis-(thio-cyanato-κN)tin(IV).

The Sn(IV) atom in the title compound, [Sn(CH3)2(NCS)2(C12H8N2)], is located on a twofold rotation axis in a distorted octa-hedral enviroment. The methyl groups are trans to each other [C-Sn-C = 175.7 (3)°], whereas the thio-cyanate groups are cis to each other.

Dimethyl-bis-(pyrazine-2-carboxyl-ato-κ(2)N(1),O)tin(IV).

In the title compound, [Sn(CH(3))(2)(C(5)H(3)N(2)O(2))(2)], the Sn(IV) atom is twice N,O-chelated by two pyrazine-2-carboxyl-ate ligands. The distorted six-coordination is completed by two tin-bound methyl C atoms. The C(2)N(2)O(2) donor set defines a skewed trapezoidal-bipyramidal geometry.

Determination of polycyclic aromatic hydrocarbons in Persian Gulf and Caspian Sea: gold nanoparticles fiber for a head space solid phase micro extraction.

A gold nanoparticles modified fused silica fiber was developed and used for the head space solid phase micro-extraction (HS-SPME) of polycyclic aromatic hydrocarbons (PAHs), including naphthalene, anthracene, acenaphthylene, phenanthrene, fluoranthene and pyrene. The effects of different parameters influencing the extraction efficiency including extraction temperature, extraction time, ionic strength, stirring rate and sample volume were examined and optimized. Linear ranges of 1-300 μg L(-1) for naphthalene, 0.

Dibromido(2,9-dimethyl-1,10-phenanthroline-κ(2)N,N')zinc.

The reaction of equimolar amounts of zinc bromide and 2,9-dimethyl-1,10-phenanthroline in dry methanol provided the title compound, [ZnBr(2)(C(14)H(12)N(2))], in good yield. The Zn(II) ion is coordinated in a distorted tetra-hedral environment by two N atoms from the chelating 2,9-dimethyl-1,10-phenanthroline ligand and two bromide ions. There is inter-molecular π-π stacking between adjacent phenanthroline units, with centroid-centroid distances of 3.

A second triclinic polymorph of bis-(μ-N-nitroso-N-phenyl-hydroxy-laminato)-κ(3)O,O':O';κ(3)O':O,O'-bis-[(N-nitroso-N-phenyl-hydroxy-laminato-κ(2)O,O')lead(II)].

The cupferronate ions in the centrosymmetric dinuclear title compound, [Pb(2)(C(6)H(5)N(2)O(2))(4)], O,O'-chelate to the two Pb(II) atoms; two of the four nitroso O atoms are also involved in bridging. The geometries of the five-coordinate Pb(II) atoms in the two independent mol-ecules are Ψ-octa-hedral; if more remote Pb⋯O inter-actions are also considered, the coordination number is increased to six for one mol-ecule and to seven for the other. Their coordination polyhedra are ill defined in the chain motif, which runs along [100].

[4-(Dimethyl-amino)-pyridine-κN(1)]tri-methyl(thio-cyanato-κN)tin(IV).

In the title monomeric trimethyl-tin(IV) isothio-cyanate-4,4-dimethyl-pyridine adduct, [Sn(CH(3))(3)(NCS)(C(7)H(10)N(2))], the Sn(IV) atom shows a trans-C(3)SnN(2) trigonal bipyramidal coordination. The Sn(IV) atom lies out of the equatorial plane by 0.033 (4) Å in the direction of the donor N atom of the N-heterocycle.

4-(Dimethyl-amino)-pyridinium tetra-chlorido(pyridine-2-carboxyl-ato-κ(2)N,O)stannate(IV).

The reaction of 4-(dimethyl-amino)-pyridine, picolinic acid and stannic chloride yields the title salt, (C(7)H(11)N(2))[SnCl(4)(C(6)H(4)NO(2))], in which the Sn(IV) atom is N,O-chelated by the picolinate ion in a cis-SnNOCl(4) octa-hedral geometry. The cation is linked to the anion by an N-H⋯O hydrogen bond.

10-Hy-droxy-benzo[h]quinolin-1-ium tetra-chlorido(pyridine-2-carboxyl-ato-κ(2)N,O)stannate(IV) methanol monosolvate.

The reaction of 4-(dimethyl-amino)-pyridine, picolinic acid and stannic chloride yields the title monosolvated salt, (C(13)H(10)NO)[SnCl(4)(C(6)H(4)NO(2))]·CH(3)OH. The Sn(IV) atom is N,O-chelated by the picolinate ion in a cis-SnNOCl(4) octa-hedral geometry. The cation is linked to the methanol solvent mol-ecule by an O-H⋯O hydrogen bond; the solvent mol-ecule itself is a hydrogen-bond donor to the uncoordinating carboxyl-ate O atom of the anion.

8-Hy-droxy-2-methyl-quinolinium tetra-chlorido(quinolin-8-olato-κ(2)N,O)stan-nate(IV).

The reaction of 8-hy-droxy-quinoline, 2-methyl-quinolin-8-ol and stannic chloride yields the protonated 8-hy-droxy-2-methyl-quinolinium species. In the title salt, (C(10)H(10)NO)[Sn(C(9)H(6)NO)Cl(4)], the Sn(IV) cation is N,O-chelated by the quinolin-8-olate anion and is further coordinated by four Cl(-) anions in a distorted cis-SnNOCl(4) octa-hedral geometry. In the crystal, the cation is linked to the anion by an O-H⋯O hydrogen bond.

2-[(Propan-2-yl-oxy)carbon-yl]quinolin-1-ium tetra-chlorido(quinoline-2-carboxyl-ato-κ(2)N,O)stannate(IV).

In the title salt, (C(13)H(14)NO(2))[Sn(C(10)H(6)NO(2))Cl(4)], the Sn(IV) cation is N,O-chelated by the quinolincarboxyl-ate unit and further coordinated by four Cl(-) anions in a distorted octa-hedral geometry. In the crystal, the 2-[(propan-2-yl-oxy)-carbon-yl]quinolin-1-ium cation is linked to the Sn complex anion by an N-H⋯O hydrogen bond.

catena-Poly[[(2,9-dimethyl-1,10-phenanthroline-κ(2)N,N')lead(II)]-di-μ-bromido].

In the title compound, [PbBr(2)(C(14)H(12)N(2))](n), the Pb(II) atom lies on a twofold rotation axis. The N-heterocycle-chelated Pb(II) atom exists in a distorted octa-hedral geometry owing to two long Pb⋯Br inter-actions [2.9562 (5) and 3.

Synthesis and characterization of 8-hydroxyquinoline complexes of tin(IV) and their application in organic light emitting diode.

A series of 8-hydroxyquinoline complexes of tin, Q(2)SnCl(2) (Q = 2-methyl-8-hydroxyquinoline, 8-hydroxyquinoline, 5,7-dibromo-8-hydroxyquinoline, 5-chloro-8-hydroxyquinoline, 5,7-dichloro-8-hydroxyquinoline and 5-nitro-8-hydroxyquinoline) were prepared by reacting stannous dichloride with 8-hydroxyquinoline and its derivatives. All complexes were characterized by elemental analysis, mass spectrometry and infrared, UV-vis and (1)H NMR spectroscopes. Furthermore, the molecular structure of a representative complex, dichlorido-bis(5-nitro-quinolin-8-olato-2N,O)tin(IV), was determined by single-crystal X-ray diffraction.

8-Hy-droxy-2-methyl-quinolinium tetra-chlorido(pyrazine-2-carboxyl-ato-κN,O)stannate(IV) methanol monosolvate.

In the title solvated salt, (C(10)H(10)NO)[SnCl(4)(C(5)H(3)N(2)O(2))]·CH(3)OH, the Sn(IV) atom is chelated by the N,O-bidentate pyrazine-2-carboxyl-ate ligand and four chloride ions, and shows a distorted octa-hedral SnNOCl(4) coordination at the metal atom. The 8-hy-droxy-2-methyl-quinolinium cation and the anion are linked to the methanol mol-ecules by O-H⋯O, O-H⋯N and N-H⋯O hydrogen bonds, generating a linear chain running along [1[Formula: see text]0]. There are two independent ion pairs and solvent mol-ecules in the asymmetric unit.

8-Hy-droxy-2-methyl-quinolinium diiodido(2-methyl-quinolin-8-olato-κN,O)zincate.

The reaction of 2-methyl-8-hy-droxy-quinoline and zinc iodide in acetonitrile affords the title salt, (C(10)H(10)NO)[Zn(C(10)H(8)NO)I(2)], in which the Zn(II) ion is coordinated by a N,O-chelating 2-methyl-quinolin-8-olate ligand and two iodide ligands in a distorted tetra-hedral geometry. The cation is linked to the anion by an O-H⋯O hydrogen bond.

10-Hy-droxy-benzo[h]quinolinium tetra-chlorido(2-methyl-quinolin-8-olato-κN,O)stannate(IV) methanol disolvate.

In the disolvated title salt, (C(13)H(10)NO)[SnCl(4)(C(10)H(8)NO)]·2CH(3)OH, the Sn(IV) atom is chelated by the N,O-bidentate 2-methyl-quinolin-8-olate ion and is further coordinated by four chloride ions, showing a distorted octa-hedral SnNOCl(4) geometry. In the crystal, the cation and anion are linked to the methanol mol-ecules by O-H⋯O and N-H⋯O hydrogen bonds.

Chlorido(8-hy-droxy-quinoline-κN,O)(quinolin-8-olato-κN,O)zinc methanol monosolvate.

In the title compound, [Zn(C(9)H(6)NO)Cl(C(9)H(7)NO)]·CH(3)OH, the Zn(II) ion is N,O-chelated by both a neutral and a deprotonated quinolin-8-ol ligand, with a chloride ligand in the apical site completing the square-pyramidal coordination geometry. The Zn(II) ion is displaced by 0.586 Å in the direction of the chloride ligand from the atoms forming the square plane.