Fast Atom Bombardment Mass Spectra Research Articles

Production of a New Biosurfactant by a New Yeast Species Isolated from Prunus mume Sieb. et Zucc.

Biosurfactants reduce surface and interfacial tension due to their amphiphilic properties and are an eco-friendly alternative for chemical surfactants. In this study, a new yeast strain JAF-11 that produces a biosurfactant was selected using drop collapse method, and the properties of the extracts were investigated. The nucleotide sequences of the strain were compared with closely related strains and identified based on the D1/D2 domain of the large subunit ribosomal DNA (LSU) and internal transcribed spacer (ITS) regions. Neodothiora populina CPC 39399T, the closest species with strain JAF-11, showed a sequence similarity of 97.75% for LSU and 94.27% for ITS, respectively. The result suggests that the strain JAF-11 represents a distinct species that cannot be assigned to any existing genus or species in the family Dothideaceae. Strain JAF-11 produced a biosurfactant reducing the surface tension of water from 72 mN/m to 34.5 mN/m on the sixth day of culture and the result of measuring the critical micelle concentration (CMC) by extracting the crude biosurfactant was found to be 24 mg/l. The molecular weight 502 of the purified biosurfactant was confirmed by measuring the fast atom bombardment mass spectrum. The chemical structure was analyzed by measuring 1H nuclear magnetic resonance (NMR), 13C NMR, and two-dimensional NMRs of the compound. The molecular formula was C26H46O9, and it was composed of one octanoyl group and two hexanoyl groups to myo-inositol moiety. The new biosurfactant is the first report of a compound produced by a new yeast strain, JAF-11.

Production, Structural Characterization, and In Vitro Assessment of the Prebiotic Potential of Butyl-Fructooligosaccharides.

Short-chain fatty acids (SCFAs), especially butyrate, produced in mammalian intestinal tracts via fermentation of dietary fiber, are known biofunctional compounds in humans. However, the variability of fermentable fiber consumed on a daily basis and the diversity of gut microbiota within individuals often limits the production of short-chain fatty acids in the human gut. In this study, we attempted to enhance the butyrate levels in human fecal samples by utilizing butyl-fructooligosaccharides (B-FOS) as a novel prebiotic substance. Two major types of B-FOS (GF3-1B and GF3-2B), composed of short-chain fructooligosaccharides (FOS) bound to one or two butyric groups by ester bonds, were synthesized. Qualitative analysis of these B-FOS using Fourier transform infrared (FT-IR) spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), nuclear magnetic resonance (NMR) and low-resolution fast-atom bombardment mass spectra (LR-FAB-MS), showed that the chemical structure of GF3-1B and GF3-2B were [O-(1-buty-β-D-fru-(2→1)-O-β-D-fru-(2→1)-O-β-D-fru-O-α-D-glu] and [O-(1-buty)-β-D-fru-(2→1)-O-β-D-fru-(2→1)-O-(4-buty)-β-D-fru-O-α-D-glu], respectively. The ratio of these two compounds was approximately 5:3. To verify their biofunctionality as prebiotic oligosaccharides, proliferation and survival patterns of human fecal microbiota were examined in vitro via 16S rRNA metagenomics analysis compared to a positive FOS control and a negative control without a carbon source. B-FOS treatment showed different enrichment patterns on the fecal microbiota community during fermentation, and especially stimulated the growth of major butyrate producing bacterial consortia and modulated specific butyrate producing pathways with significantly enhanced butyrate levels. Furthermore, the relative abundance of Fusobacterium and ammonia production with related metabolic genes were greatly reduced with B-FOS and FOS treatment compared to the control group. These findings indicate that B-FOS differentially promotes butyrate production through the enhancement of butyrate-producing bacteria and their metabolic genes, and can be applied as a novel prebiotic compound in vivo.

English

The solvent extracts of 368 plant parts from 191 different species cultivated in Tsukuba (Ibaraki Prefecture, Japan) were previously screened for aryl hydrocarbon receptor (AhR) transformation inhibitory activity. It was observed that the leaf extract of Mallotus japonicus had strong activity. To clarify the antidioxin phytochemical, a 70% acetone extraction from the leaves was fractionated with three kinds of solvent (n-hexane, ethyl acetate, 1-butanol) in order of increasing polarity. The fractions of ethyl acetate and 1-butanol with strong antidioxin activity were purified by preparative high performance liquid chromatography in combination with AhR transformation assays by a cell-free system using a rat hepatic cytosolic fraction. The structures of isolated compounds were elucidated by nuclear magnetic resonance (NMR) techniques and fast atom bombardment mass spectra. As a result, six compounds (phyllanthusiin D, quercetin, quercitrin, isoquercitrin, rutin, and kaempferol-3-O-rutinoside) as the active components were isolated. The compounds suppressed AhR transformation in a concentration-dependent manner, with 50% inhibitory concentration (IC50) values of 0.12 µM (phyllanthusiin D), 0.45 µM (quercitrin), 0.97 µM (isoquercitrin), and 16 µM (rutin) against 1 nM 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced AhR transformation. Quercetin and kaempferol-3-rutinoside exhibited very weak activity. Thus, phyllanthusiin D, which is a hydrolysable tannin, exhibited the greatest activity. This is the first report to demonstrate the antidioxin activity of a tannin. Key words: Mallotus japonicus, aryl hydrocarbon receptor (AhR) transformation, flavonol, tannin. &nbsp

Effect of gamma-irradiation on thermal decomposition kinetics, X-ray diffraction pattern and spectral properties of tris(1,2-diaminoethane)nickel(II)sulphate

Tris(1,2-diaminoethane)nickel(II)sulphate was prepared, and characterised by various chemical and spectral techniques. The sample was irradiated with 60Co gamma rays for varying doses. Sulphite ion and ammonia were detected and estimated in the irradiated samples. Non-isothermal decomposition kinetics, X-ray diffraction pattern, Fourier transform infrared spectroscopy, electronic, fast atom bombardment mass spectra, and surface morphology of the complex were studied before and after irradiation. Kinetic parameters were evaluated by integral, differential, and approximation methods. Irradiation enhanced thermal decomposition, lowering thermal and kinetic parameters. The mechanism of decomposition is controlled by R3 function. From X-ray diffraction studies, change in lattice parameters and subsequent changes in unit cell volume and average crystallite size were observed. Both unirradiated and irradiated samples of the complex belong to trigonal crystal system. Decrease in the intensity of the peaks was observed in the infrared spectra of irradiated samples. Electronic spectral studies revealed that the M–L interaction is unaffected by irradiation. Mass spectral studies showed that the fragmentation patterns of the unirradiated and irradiated samples are similar. The additional fragment with m/z 256 found in the irradiated sample is attributed to S8+. Surface morphology of the complex changed upon irradiation.

Abietane, Labdane, and Pimarane Diterpenoids from the Pulp of Torreya nucifera

Torreya nucifera is an evergreen coniferous tree, widely distributed in Japan, Korea, and People's Republic of China. Its seeds exhibit significant insecticidal activity. The fruits of this evergreen are widely used in folk medicine for the treatment of tapeworm infestation in Korea and to induce abortion in Japan, but most chemical studies of T. nucifera have focused on its leaves and wood. A number of sesquiterpenoids, labdane and abietane diterpenoids, ligans, and flavonoids were identified as active secondary metabolites [1–8]. T. nucifera is a Taxaceae plant endemic to Korea, Japan, and China. In order to compare its constituents with those of Taxus spp. and to understand their taxonomic relationship, we investigated the chemical composition of Torreya nucifera. Five diterpenoids were isolated for the first time from the pulp of the title plant, including one labdane diterpenoid, two abietane diterpenoids, and two pimarane-type diterpenoids. Their structures were established on the basis of 1D and 2D NMR spectrascopic analysis. We report herein the isolation and structure characterization of these diterpenoids and detailed the 1H and 13C NMR data of compounds 1–5. Melting points were measured with an MRK micro-melting point apparatus and were uncorrected. Column chromatographic separations were carried out using silica gel (300–400 mesh, Qingdao Haiyang Chemical Group Corporation, Qingdao, P. R. China). Na2SO4 was the drying agent used in all workup procedures. Solvents and reagents of analytic grade (reagent grade used without further purification) were purchased from commercial sources. TLC was performed on precoated silica gel F254 glass-backed plates without activation. Fractions were monitored by TLC with visualization under UV light (254 and 365 nm) and by dipping the plates into a solution of 10% (v/v) H2SO4 in EtOH followed by heating on a hot plate for 5 min. Analytical HPLC was performed on a Waters 2695 separation module coupled to a 2996 photodiode array detector. Preparative HPLC was carried out on a Waters Delta Prep 3000 instrument coupled to a UV 2487 dual absorbance detector. Analytical HPLC was performed using two Whatman partisil 10 ODS-2 analytical columns (4.6 250 mm) in series. Preparative HPLC was performed using a partisil 10 ODS-2 MAG-20 preparative column (9.4 250 mm). The products were eluted with a 50 min linear gradient of acetonitrile (25 to 100%) in water at a flow rate of 3 mL/min (preparative HPLC). Positive ion fast atom bombardment mass spectra (FAB-MS) was obtained with a Vacuum Generators ZAB-HS instrument. All NMR spectra were recorded on a Varian Unity INOVA 600 or 500 NMR spectrometer equipped with a 5 mm probe at ambient temperature in CDCl3 solution. The 1H and 13C chemical shifts were referenced relative to TMS residue. Typical one-dimensional (1D) 1H and 13C spectra were acquired under standard condition on a Varian Unity INOVA 500/600 spectrometer operating at 499.861/599.913 and 125.690/150.848 MHz, respectively. 1H and 13C chemical shifts are expressed in the scale as parts per million (ppm).

Thioglycerol matrix interactions in the positive ion fast atom bombardment mass spectrometry of several Hantzsch and Biginelli ester derivatives of boronic acids

Fast atom bombardment (FAB) ionization is a valuable tool for analyzing non-volatile or thermally labile compounds when harder ionization methods (EI or CI) have been unsuccessful. Unexpected interactions between matrix and analyte may, however, occur in FAB ionization leading to the formation of artifacts whose structures have to be determined. We used esters synthesized by our research group following green chemistry protocols. Artifacts relating to the target molecules were produced in the solvent cage using positive ion FAB using thioglycerol as the matrix and analyzed by accurate mass measurement. Through interactions between thioglycerol and the boron atom, various adducts associated with boron-containing Hantzsch and Biginelli ester derivatives appeared in the FAB mass spectra. These interactions must arise in a solvent cage involving a Lewis acid-base bond. Accurate mass determinations of these adducts confirmed the presence of the target molecules. Interactions between the thioglycerol matrix and the eleven boron-containing Hantzsch and Biginelli ester derivatives in addition to the three reagents were seen in their FAB(+) spectra. These interactions, together with their accurate mass determinations, allowed us to determine the structures of the new molecules.

Mass-spectrometric study of the formation of silver nanoclusters in polyether media: 2. Fast atom bombardment and modeling

Within the problem of the synthesis of silver nanoclusters and nanoparticles in polyether media, systems containing silver nitrate AgNO3 and low-molecular-weight polyethers, poly(ethylene glycol) PEG-400 or oxyethylated glycerol OEG-5, were studied by fast atom bombardment (FAB) mass spectrometry. The formation of stable clusters of polyether oligomers (M m ) with silver cations M m · Ag+ was shown, in agreement with the previous data of laser desorption/ionization. Quantum-chemical DFT calculations have shown that the M m · Ag+ clusters are stabilized by wrapping of the polyether chain around the silver cation with the cation coordinating ether oxygen atoms. Silver nanoclusters were not found in the FAB mass spectra of liquid systems, but Ag n + clusters were detected for silver nanoparticles separated from the reaction medium. No products of chemical transformations of PEG-400 or OEG-5 were observed by FAB. A plausible mechanism of the reduction of silver cations involving nitrate anions is discussed.

Studies on reactions of some ruthenium sulfoxide bipyridyl complexes with 1,4-bis(salicylidene)phenylenediamine ligand used as spacer

A dinucleating spacer 1,4-bis(salicylidene)phenylenediamine (SALPHEN) derived from 1,4-phenylenediamine and salicylaldehyde has been synthesized and characterized. The ruthenium(II) sulfoxide derivative of 2,2′-bipyridine or 1,10-phenanthroline on reaction with this ligand resulted in the formation of eight dinuclear complexes, which were characterized by elemental analyses, conductivity measurements, magnetic susceptibility, FT-IR, fast atom bombardment-mass spectra, electronic spectroscopy, 1H-NMR, 13C{1H}-NMR, and 2D-NMR spectra (HETCOR). The prepared complexes have two different formulations, [{trans-RuCl2(so)(N–N′)}2(μ-SALPHEN)] and [{cis-RuCl2(so)(N–N′)}2(μ-SALPHEN)], where so = dimethyl sulfoxide (DMSO)/tetramethylene sulfoxide (TMSO), N–N′ = 2,2′-bipyridine/1,10-phenanthroline, and SALPHEN = 1,4-bis(salicylidene)phenylenediamine. Two moles of ruthenium sulfoxide bipyridine precursor were coordinated to the bidentate SALPHEN through nitrogen. All the complexes possess antibacterial activity against Escherichia coli in comparison to Chloramphenicol.

Synthesis and Characterization of New 2-Oxo-azetidine Derivatives

Several new N-[(4-aryl-3-chloro-2-oxo-azetidine)acetamidyl]-5-nitroindazoles 4a–l were synthesized from N-(arylidene amino acetamidyl)-5-nitroindazoles 3a–l. The structures of all these compounds were confirmed by infrared, 1H NMR, 13C NMR, and fast atom bombardment–mass spectra and also by microanalytical data.

A new prenylated xanthone from Garcinia xipshuanbannaensis Y.H. Li

A new prenylated xanthone, named bannaxanthone I (1), has been isolated from the leaves of Garcinia xipshuanbannaensis, along with five other known compounds, bannaxanthone E (2), mangostinone (3), tovophyllin A (4), garcinone E (5), and γ-mangostin (6). The structure of the new compound was elucidated on the basis of high-resolution fast atom bombardment mass spectra (HRFABMS), 1D-and 2D-NMR experiments, including heteronuclear multiple bond connectivity (HMBC), heteronuclear single quantum coherence (HSQC) and 1H–1H-COSY (correlated spectroscopy, COSY).

ChemInform Abstract: Formation and Extraction of Very Large All-Carbon Fullerenes.

A series of very large all-carbon fullerenes has been successfully extracted with quinoline from fullerene-rich carbon soot produced by vaporization of graphite with contact arc. The present extracts (black powder) are not soluble in benzene or toluene, which are normally used as extraction solvents from C{sub 60} and C{sub 70}. The fast atom bombardment (FAB) mass spectra of the so-obtained extracts reveal that the extracts are found to contain very large fullerenes as large as C{sub 300}. A series of large even-numbered fullerenes C{sub 70+2n} (90 {ge} n {ge} 1) is detected in the FAB mass spectra. The results indicate that these fullerenes are not fragments of very large fullerenes but are actually present in the graphite soot. It is suggested that giant fullerenes (> C{sub 300}) may also be present in the present quinoline extract.

Synthesis and spectral characterization of Cu(II) complexes of some thio-Schiff bases of acyl pyrazolone analogues

A series of tridentate pyrazolone-based thio-Schiff bases were synthesized by the interaction of 4-acyl/aroyl pyrazolones with thiosemicarbazide in an ethanolic medium. All of these ligands were characterized on the basis of elemental analysis, infrared (IR), 1H- and 13C-NMR data. Nuclear magnetic resonance (NMR) suggests the amine-one form of ligand in solution at room temperature. Copper Schiff-base complexes, [Cu(L)(H2O)], have been prepared by the interaction of the aqueous solution of copper sulfate pentahydrate with hot ethanolic solution of the appropriate ligand. The resulting complexes have been characterized by elemental analysis, metal content determination, molar conductance, fast atom bombardment mass spectra, magnetic measurements, thermogravimetric analysis (TGA), IR, and electronic spectral studies. Thermal stability, heat capacity, and activation energy of thermal degradation for these complexes were determined by TGA, differential thermal analysis, and differential scanning calorimetry. Suitable structures are proposed for these complexes.

DNA interaction studies of ruthenium(II) polypyridyl complex : [Ru(dmb)2(ITAP)](ClO4)2 (ITAP = isatino [1,2-b]-1,4,8,9-tetraazatriphenylene)

A new ligand ITAP and its complex [Ru(dmb)2(ITAP)](ClO4)2 (ITAP = isatino [1,2-b]-1,4,8, 9-tetraazatriphenylene, dmb = 4,4′-dimethyl-2,2′-bipyridine) have been synthesized and characterized by elemental analysis, Fast atom bombardment mass spectra, Electrospray mass spectra, and 1H NMR. Thermal denaturation and absorption titration experiments show the complex binds to calf thymus DNA (CT-DNA) with moderate affinities. Viscosity measurements and thermal denaturation indicate that the DNA-binding mode could be intercalative interaction. The Ru(II) complex in the presence of plasmid pBR322 DNA has been found to promote the cleavage of plasmid pBR322 DNA from the supercoiled Form I to the open circular Form II upon irradiation. Mechanisms for DNA cleavage by the complex were also investigated.

Theoretical study of the experimental coordination behavior of N-(2-aminophenyl)- d- glycero- d- gulo-heptonamide to Hg(II) ion

The reactivity of N-(2-aminophenyl)- d- glycero- d- gulo-heptonamide ( adgha), with the group 12 cations, Zn(II), Cd(II), and Hg(II), was studied in DMSO- d 6 solution. The studied system showed a selective coordination to Hg(II), and the products formed were characterized by 1H and 13C NMR in DMSO- d 6 solution and fast atom bombardment (FAB +) mass spectra. The expected coordination compounds, [Hg( adgha)](NO 3) 2 and [Hg( adgha) 2](NO 3) 2, were observed as unstable intermediates that decompose to bis-[2-( d- glycero- d- gulo-hexahydroxyhexyl)-benzimidazole-κ N]mercury(II) dinitrate, [Hg( ghbz) 2](NO 3) 2. The chemical transformation of the complexes was followed by NMR experiments, and the nature of the species formed is sustained by a theoretical study done using DFT methodology. From this study, we propose the structure of the complexes formed in solution, the relative stability of the species formed, and the possible role of the solvent in the observed transformations.

Elucidation of Charge Transport and Optical Parameters in the Newly 1CR-dppm Organic Crystalline Semiconductors

As a part of a wide plan concerning the novel organic materials, a set of newly organic semiconductors has been obtained in our laboratories. In this paper, a clear overview was reported for elucidating the preparation processes of the chromium−copper mixed crystals. In line with the novel pyrazole diphenylphosphino-methane (M-dppm) derivatives, two mixed organic semiconductors were obtained: the one cupper apyrazole ring compound 5a, C78H74CrCuN4O3P4 (1CR-dppm) and the two cupper apyrazole ring compound 6a, C78H74CrCu2N4O4P4 (2CR-dppm). The structure of the obtained crystals were examined by the X−ray diffraction, and the structures of the two mentioned compounds were discussed based on elemental analysis (EA), IR, 1H NMR, 31P NMR spectroscopic data, and fast atom bombardment mass spectra. The compounds under investigation show typical semiconductor behavior due to of delocalization of the π-electrons in the structure. The temperature dependence of charge transports and optical parameters for the 5a crys...

The relationship between the metabolism of sphingomyelin species and the hemolysis of sheep erythrocytes induced by Clostridium perfringens α-toxin

Clostridium perfringens alpha-toxin induces the hemolysis of sheep erythrocytes by activating the metabolism of sphingomyelin (SM) via a GTP binding protein in membranes. alpha-Toxin stimulated the formation of 15-N-nervonoyl sphingosine (C24:1-ceramide), which was identified by positive ion fast atom bombardment-MS and 1H-NMR spectroscopy. C24:1-ceramide stimulated the toxin-induced hemolysis of saponin-pretreated sheep erythrocytes and increased the production of sphingosine 1-phosphate (S1P) in the cells, but N-lignoceroyl sphingosine did not. These events elicited by the toxin in the presence of C24:1-ceramide were significantly attenuated by treatment with dihydrosphingosine, a sphingosine kinase inhibitor. TLC showed that the level of C24:1-ceramide was highest among the ceramides with an unsaturated bond in the fatty acyl chain in the detergent-resistant membranes (DRMs). The toxin specifically bound to DRMs rich in cholesterol, resulting in the hydrolysis of N-nervonoic sphingomyelin (C24:1-SM) in DRMs. Treatment of the cells with pertussis toxin (PT) inhibited the alpha-toxin-induced formation of C24:1-ceramide from C24:1-SM in DRMs and hemolysis, indicating that endogenous sphingomyelinase, which hydrolyzes C24:1-SM to C24:1-ceramide, is controlled by PT-sensitive GTP binding protein in membranes. These results show that the toxin-induced metabolism of C24:1-SM to S1P in DRMs plays an important role in the toxin-induced hemolysis of sheep erythrocytes.

Study of factors governing negative molecular ion yields of amino acid and peptide in FAB, MALDI and ESI mass spectrometry

The factors governing negative and/or positive molecular ion yields of amino acids and peptides in the soft ionization methods of fast atom bombardment (FAB), matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI) mass spectrometry have been examined. The results obtained have been interpreted from the standpoint of two different components, namely desorption and ionization, by relating the ion yields to physicochemical properties of amino acid and peptides. The negative-ion yields of amino acids in FAB were found to be dependent on gas-phase acidity and aliphatic/hydrophobicity. In MALDI, a linear correlation was observed between negative-ion yields and gas-phase acidity of amino acids. In both FAB and MALDI mass spectra of peptides, the presence of aspartic acid residues tended to enhance the negative-ion yields. The presence of aliphatic/hydrophobic residues in FAB or aromatic amino acid residues in MALDI enhanced the negative-ion yields of peptides. In ESI, the charge state distributions of multiply-protonated peptides were dependent on the number of basic sites and their position in the sequence, while those of multiply-deprotonated peptides were dependent on the number of acidic sites. The total ion yields in ESI were governed by hydrophobicity of peptides and efficiency of acquiring the charge(s). The results suggest that the ion yields were governed by two independent processes, namely ionization and desorption, regardless of the ionization methods used.

Structural Determination of Two Active Compounds That Bind to the Muscarinic M3 Receptor in Beer

It is known that beer accelerates gastrointestinal motility in humans. Our previous studies showed that beer congener stimulates gastrointestinal motility by directly stimulating the muscarinic M3 receptor. Further, we isolated 2 active compounds (compounds A and B) from beer by liquid chromatography. The objective of the present study was to identify the 2 active compounds that bind to the muscarinic M3 receptor in beer. Structural analyses of the active compounds were performed by fast atom bombardment mass spectra, 1H-nuclear magnetic resonance (NMR), and 13C-NMR spectroscopy. Active compounds were chemically synthesized from p-coumaric acid and agmatine as starting materials. Binding activity to the muscarinic M3 receptor was used to confirm the activity of the synthetic compounds. It was identified that 2 active compounds had the same structural characteristics: stereoisomers (cis-isomer and trans-isomer), molecular weight=550 and molecular formula=C28H38N8O4. Trans-isomer (compound B) was identified as the known substance hordatine A, a kind of phytoalexin in barley, and cis-isomer (compound A) was found to be a novel compound (tentatively referred to as aperidine). Both naturally present and chemically synthesized aperidine (compound A) and hordatine A (compound B) were demonstrated to have potent binding activities to the muscarinic M3 receptor. The 2 active compounds isolated from beer, namely aperidine (compound A) and hordatine A (compound B), have structurally and functionally been identified as active entities of binding to the muscarinic M3 receptor.

ANDP-2, A Novel Acrinol Degradation Product by Light

To clarify the degradation pathway of acrinol by light, isolation and identifi cation of acrinol degradation products (ANDP) were attempted. ANDP2, on eo ft he ANDPs, was isolated by extraction with methanol from cloths dampened with acrinol solution, and purified by column chromatography on Diaion HP-10, Sephadex LH-20 and G25. Th es tructural elucidation of ANDP-2 was examined by infrared, 1 H-NMR, 13 C-NMR and Fast atom bombardment mass (FAB-MS) spectra studies. From the spectroscopic data, the structure of ANDP-2 was determined to be 4-amino-6-ethoxyl-2,3dicarboxyquinoline, that was found to be a novel degradation product of acrinol by light. The solution of ANDP-2 has fluorescence with a blue color, though that of acrinol has fluorescence with green. ANDP-2 did not show growth inhibition at a concentration of 100µg/ml against Gram-positive, -negative bacteria, yeast and fungi.

Application of a multi-dentate amphiphilic compound to transfer silver nanoparticles into an organic solvent

A multi-dentate amphiphilic compound, 3,3′-(dodecylazanediyl)-bis-[ N-(2-aminoethyl)propanamide] (12C–2NH 2) has been synthesized. The molecular structure was characterized by Fourier transform infrared (FT-IR) spectroscopy, ultraviolet–visible (UV–vis) spectra, nuclear magnetic resonance (NMR) spectra, and fast atom bombardment mass (FAB-MS) spectra. 12C–2NH 2 was employed to stabilize silver nanoparticles. Surface properties and stability of silver nanoparticles were controlled by adjusting the 12C–2NH 2 to silver (0) molar ratio. 12C–2NH 2 was also applied to transfer silver nanoparticles from an aqueous to an organic phase. The transfer efficiency depends on 12C–2NH 2 concentration. When 12C–2NH 2 to silver (0) molar ratio was 2:1, the highest efficiency of phase transfer to toluene was obtained. These 12C–2NH 2 stabilized silver nanoparticles are very stable over a period of four days in toluene.