Search results for "ethylenediamine"
showing 10 items of 142 documents
Peroxodisulfate as a chemical initiator for methacrylate-ester monolithic columns for capillary electrochromatography
2008
Organic monolithic stationary phases for CEC were synthesized in situ in fused-silica capillaries. Polymerization mixtures were composed of butyl methacrylate, ethylene dimethacrylate, and [2-(methacryloyloxy)ethyl]trimethyl ammonium chloride in the presence of a porogenic solvent, using ammonium peroxodisulfate as chemical initiator, and N,N,N',N'-tetramethylethylenediamine to activate the reaction. The influence of the amount of initiator, temperature, and composition of porogenic solvent on the physical and chromatographic properties of monolithic stationary phases has been investigated. A minimum plate height of 14.5 microm was obtained at 18 wt% of 1,4-butanediol in the polymerization …
Inulin-Ethylenediamine Coated SPIONs Magnetoplexes: A Promising Tool for Improving siRNA Delivery.
2015
An inulin based polycation (Inu-EDA) has been synthesized by the grafting of ethylenediamine molecules onto inulin backbone. The obtained inulin copolymer has been though to coat SPIONs (IC-SPIONs) and obtain stable magnetoplexes by complexation of IC-SPIONs with a model duplexed siRNA, for improving oligonucleotide transfection efficiency.The physical-chemical characteristics of IC-SPIONs and IC-SPIONs/siRNA magnetoplexes have been investigated by scanning and transmission electron microscopies, dynamic light scattering, FT-IR and qualitative surface elementary analysis. Cell compatibility and internalization in vitro of IC-SPIONs have been evaluated by MTS and fluorescence microscopy resp…
Separation of chelating agents as copper complexes by capillary zone electrophoresis using quaternary ammonium bromides as additives in N-methylforma…
2006
This study presents the use of quaternary ammonium bromides as additives in N-methylformamide (NMF) for the separation and quantification of chelating agents as copper complexes by capillary zone electrophoresis (CZE). The new quaternary ammonium bromides were synthesized in our laboratory and used for the first time for CZE applications performed in NMF media. The methods were developed and optimized for determination of six chelating agents (trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid (CDTA), diethylenetriaminepentaacetic acid (DTPA), ethylenediaminetetraacetic acid (EDTA), N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid (HEDTA), nitrilotriacetic acid (NTA) and trieth…
On the synthesis and characterization of layered antimony(III) phosphate and its interaction with moist ammonia and amines
1998
Samples of antimony(III) phosphate, a layered material, were prepared at room temperature, using the two allotropic forms of Sb2O3, layered valentinite and cubic senarmontite. The compounds were characterized by infrared spectroscopy, X-ray diffraction, and thermogravimetric–differential thermal analysis. Solids exposed to ammonia, ethylenediamine, or hydrazine vapors also were studied. The interaction between SbPO4 and the bases always led to the formation of stoichiometric amounts of Sb2O3 and hydrogen phosphate(–2) salts of the bases. With ammonia, the SbPO4 raw materials gave rise to valentinite or senarmontite, depending on which Sb2O3 allotropic form was used to prepare antimony phosp…
Determination of alternative and conventional chelating agents as copper(II) complexes by capillary zone electrophoresis—The first use of didecyldime…
2006
Abstract A capillary zone electrophoresis (CZE) method for analyzing 11 chelating agents [β-alaninediacetic acid (β-ADA), trans-1,2-diaminocyclohexane- N , N , N ′, N ′-tetraacetic acid (CDTA), diethylenetriaminepentaacetic acid (DTPA), ethylenediaminetetraacetic acid (EDTA), N -(2-hydroxyethyl)ethylenediamine- N , N ′, N ′-triacetic acid (HEDTA), N -(2-hydroxyethyl)iminodiacetic acid (HEIDA), iminodiacetic acid (IDA), methylglycinediacetic acid (MGDA), nitrilotriacetic acid (NTA), 1,3-diaminopropane- N , N , N ′, N ′-tetraacetic acid (PDTA) and triethylenetetraaminehexaacetic acid (TTHA)] as negatively charged copper(II) complexes has been established. Both conventional and alternative che…
Colorimetric determination of arylamines and sulphonamides by diazotization and coupling in a micellar solution
1989
Abstract The use of a micellar solution as a means for improving the colorimetric determination of arylamines by diazotization and coupling is studied. Sodium dodecylsulphate (SDS), Triton X-100 (TX-100) and N -cetylpyridinium chloride (NCPC), together with the diazotizable substances aniline and sulphanilic acid and the coupling agents 1-naphthylamine and N -(1-naphthyl)ethylenediamine are used as model compounds. The protonation constants of the dyes follow the order SDS>H 2 O>TX-100>NCPC. In an SDS micellar solution the coupling rate increases greatly, allowing the rapid formation of the protonated dyes in an acetate buffer. Other advantages are the possibility of analysing very non-pola…
Outer and inner coordination sphere chemistry of polyazacyclophane platinum(II) complexes. Crystal structure of [PtBr4]2(H4L1) · H2O (L1 = 2,6,9,13-t…
1997
Abstract The interaction of PtCl42− with the new azaparacyclophane 2,5,8,11-tetraaza[12]paracyclophane (L2) has been studied by 1H, 13C and 195Pt NMR spectroscopy. Three different complexes are detected as a function of pH, all of them presenting cis-arrangement of nitrogen donors and chloride anions. In the first one, formed at acidic pH, the central nitrogen atoms of the macrocyclic are coordinating to Pt(II) while the benzylic nitrogens remain protonated. Deprotonation of these nitrogens brings about a reorganisation of the complex, and the platinum is then coordinated by one benzylic nitrogen and the consecutive nitrogen in the macrocycle. This process can be monitored by NMR. Finally, …
Decacyclene as complexation manifold: synthesis, structure and properties of its Fe2 and Fe4 slipped triple-decker complexes.
2006
Reaction of [(eta(5)-Me4EtC5)Fe(II)Cl(tmeda)] (tmeda = N,N,N'N'-tetramethylethylenediamine) with a polyanion solution of decacyclene (1) results in the formation of the triple-deckers [{(eta(5)-Me4EtC5)Fe}2-mu2-(eta(6):eta(6)-decacyclene)] (3) and [{(eta(5)-Me4EtC5)Fe}4-mu4-(eta(6):eta(6):eta(6):eta(6)-decacyclene)] (4). Metal complexation in 3 and 4 occurs on opposite faces of the pi perimeter in an alternating mode. The decacyclene ring adopts a gently twisted molecular propeller geometry with twofold crystallographic symmetry (C2). Complex 4 crystallizes in the chiral space group C222(1); the investigated crystal only contains decacyclene rings with M chirality. The handedness can be ass…
Synthesis, characterization and crystal structure of the bimetallic cyano-bridged [(η5-C5H5)(PPh3)2Ru(μ-CN)Ru(PPh3)2(η5-C5H5)][PF6]
2005
Abstract The bimetallic cyano-bridged [(η 5 -C 5 H 5 )(PPh 3 ) 2 Ru(μ-CN)Ru(PPh 3 ) 2 (η 5 -C 5 H 5 )][PF 6 ] ( 1 ) was prepared by reaction of [(η 5 -C 5 H 5 )(PPh 3 ) 2 RuCl] with N , N ′-bis(cyanomethyl)ethylenediamine. The single crystal structure determined by X-ray diffraction showed crystallization on the triclinic P1 space group with a perfect alignment of the cyanide bridges. This accentric crystallization was explored having in view the NLO properties at the macroscopic level, determined by the Kurtz Powder technique. Besides the very low efficiency values for the second harmonic generation, the value obtained for the bimetallic complex 1 showed to be higher than one of the parent…
Oxidative DNA cleavage by copper ternary complexes of 1,10-phenanthroline and ethylenediamine-sulfonamide derivatives
2009
Abstract Ternary copper(II) complexes (1–3) of 1,10-phenanthroline and ethylenediamine-R-sulfonamide derivatives (R = benzene, toluene and naphthalene rings) have been synthesized and characterized with the aid of X-ray diffraction and spectroscopic and electrochemical techniques. The crystal structures of the complexes show that the coordination polyhedron around copper(II) is distorted square planar. Both 1,10-phenanthroline and ethylenediamine-R-sulfonamide act as bidentate ligands. The three structures are stabilized by π–π stacking interactions. The interaction of the complexes with calf thymus DNA has been investigated by thermal denaturation studies which indicated that DNA was stabi…