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1. Interactions of Nonaqueous Solvents with Textile Fibers : Part I: Effects of Solvents on the Mechanical Properties of a Polyester Yarn

Author:
Arthur S. Ribnick; Hans-Dietrich Weigmann; Ludwig Rebenfeld
Source:
Textile research journal 1972 v.42 no.12 pp. 720-726
ISSN:
0040-5175
Subject:
acetone; acetonitrile; dioxane; extensibility; fabrics; mechanical properties; methylene chloride; modulus of elasticity; nitrobenzenes; polyethylene terephthalates; shrinkage; solubility; solvents; textile fibers; trichloroethylene; yams; yarns
Abstract:
... In order to provide a rational basis upon which future developments in nonaqueous finishing and other processing of textile materials may be based, a basic study is being undertaken of the interactions between textile fibers and a wide spectrum of organic solvents. In this paper are reported the effects on mechanical properties of a polyester yam of 26 organic solvents differing widely in chemical ...
DOI:
10.1177/004051757204201205

2. Interactions of Nonaqueous Solvents with Textile Fibers : Part II : Isothermal Shrinkage Kinetics of a Polyester Yarn

Author:
Arthur S. Ribnick; Hans-Dietrich Weigmann; Ludwig Rebenfeld
Source:
Textile research journal 1973 v.43 no.3 pp. 176-183
ISSN:
0040-5175
Subject:
acetonitrile; activation energy; dimethylformamide; fabrics; glass transition temperature; polyesters; shrinkage; solvents; tetrachloroethylene; textile fibers; toluene; trichloroethylene; yams
Abstract:
... The kinetics of the shrinkage of a drawn polyester yam in a number of organic solvents, including toluene, acetonitrile, dimethylformamide (DMF), trichloroethylene, perchloroethylene, and tetrachloroethane, were investigated at several temperatures. The shrinkage process proceeds at a maximum rate after an induction period which is believed to be associated with diffusion of the solvent into the f ...
DOI:
10.1177/004051757304300308

3. Acidic Properties of Kaolinite in Water and Acetonitrile

Author:
R. H. Loeppert; L. W. Zelazny; B. G. Volk
Source:
Soil Science Society of America journal 1977 v.41 no.6 pp. 1101-1106
ISSN:
0361-5995
Subject:
acetonitrile; acidity; acids; aluminum; cations; clay; electrodes; kaolinite; soil; solvents; titration
Abstract:
... Potentiometric titration of weakly acidic sites on soil clays is limited in aqueous media by the acidic property of water which prevents sharp endpoints. Generally, it is not possible to obtain sharp endpoints in aqueous systems for acids with pKₐ > 8. In this study, kaolinite with K, H, or Al as the saturating cation was successfully titrated in water and acetonitrile using the glass-calomel elec ...
DOI:
10.2136/sssaj1977.03615995004100060017x

4. Pyrolysis-Gas Chromatography-Mass Spectrometry of Soil Humic Fractions: I. The Low Boiling Point Compounds

Author:
F. Martin; C. Saiz-Jimenez; A. Cert
Source:
Soil Science Society of America journal 1977 v.41 no.6 pp. 1114-1118
ISSN:
0361-5995
Subject:
Haplorthods; Hapludults; Podzols; Rhodoxeralfs; acetaldehyde; acetic acid; acetone; acetonitrile; benzene; boiling point; ethane; ethylene; fulvic acids; furfural; gas chromatography-mass spectrometry; humic acids; methane; phenol; polysaccharides; propane; propylene; proteins; pyridines; spectrometers; toluene
Abstract:
... Pyrolysis-gas chromatography-mass spectrometry studies of fulvic and humic acids from different soils: Calcic Rhodoxeralf, Typic Xerochrept, Typic Chromoxeret, Andic Hapludult, Humic Haplorthod, Typic Haplorthod and a Canadian Orthic Humo-Ferric Podzol were made. Samples were pyrolyzed at 700°C for 10 sec, and low boiling point compounds were separated in a Chromosorb 102 column. Peaks were identi ...
DOI:
10.2136/sssaj1977.03615995004100060020x

5. Facile Synthesis and Crystal Structure of [(PhSO2 N)2 WVI Cl2 (CH3CN)2] - the Oxidative Imination of W(CO)6 by N,N-Dichlorophenylsulphonamide

Author:
Herbert W. Roesky; Jörg Sundermeyer,; Jürgen Schimkowiak; Peter G. Jones; Mathias Noltemeyer; Tina Schroeder; George M. Sheldrick
Source:
Zeitschrift für Naturforschung 1985 v.40 no.6 pp. 736-739
ISSN:
1865-7117
Subject:
acetonitrile; carbon tetrachloride; crystal structure; crystallization; crystals; tungsten
Abstract:
... The reaction of N,N-dichlorophenylsulphonamide with tungsten hexacarbonyl in refluxing CCl₄ leads in good yield to the yellow polymeric complex [(PhSO₂N)₂WCl₂]ₓ, which may be converted to the octahedral nitrene complex [(PhSO₂N)₂WCl₂(CH₃CN)₂] by recrystallisation from aceto­nitrile. Crystals of the acetonitrile complex are triclinic, space group P 1̅, a = 820.7(2), b = 1128.8(3), c = 1286.9(3) pm, ...
DOI:
10.1515/znb-1985-0608

6. Recovery and Analysis by HPLC of Benzoyl Peroxide Residues in Nylon Carpet Fibers

Author:
J. Caldwell; T. Perenich
Source:
Textile research journal 1987 v.57 no.6 pp. 346-350
ISSN:
0040-5175
Subject:
acetonitrile; acne; aqueous solutions; benzoic acid; fabrics; high performance liquid chromatography; humidity; nylon; pH; plastics; sonication; temperature; textile fibers; yams; yarns
Abstract:
... The purposes of this research were to investigate the fate of benzoyl peroxide (BP) and benzoic acid (BA) on exposed nylon carpet samples and to develop extraction and chromatographic techniques to identify BP and BA on nylon 6 carpet fibers. For this research, ANSO-IV nylon 6 staple carpet yams from Allied Fibers and Plastics were used. The carpet yarns were constructed into single bar, circular ...
DOI:
10.1177/004051758705700605

7. Determination of 1,2-Dibromoethane (EDB) in Field Soils: Implications for Volatile Organic Compounds

Author:
B. L. Sawhney; J. J. Pignatello; S. M. Steinberg
Source:
Journal of environmental quality 1988 v.17 no.1 pp. 149-152
ISSN:
0047-2425
Subject:
acetone; acetonitrile; desorption; detection limit; gas chromatography; methanol; micropores; nitrogen; sediments; solid phase extraction; temperature; volatile organic compounds
Abstract:
... A method is described for determining 1,2-dibromoethane (EDB) in soils previously fumigated with EDB. The procedure involves extraction of soil with methanol at 75°C for 24 h in a sealed vial, followed by gas chromatographic analysis of the extract. Reproducibility of the method was demonstrated using replicated samples by separate analysts, and the detection limit was ≤1.8 µg kg⁻¹. Acetone and ac ...
DOI:
10.2134/jeq1988.00472425001700010025x

8. Rapid purification of wheat glutenin for reversed-phase high-performance liquid chromatography: comparison of dimethyl sulfoxide with traditional solvents

Author:
Burnouf, T.; Bietz, J.A.
Source:
Cereal chemistry 1989 v.66 no.2 pp. 121-127
ISSN:
0009-0352
Subject:
acetic acid; glutenins; globulins; albumins; ethanol; wheat flour; gliadin; dimethyl sulfoxide; durum wheat; dimethylformamide; urea; solvents; food composition; wheat protein; winter wheat; liquid chromatography; lactic acid
Abstract:
... Nondefatted and defatted wheat flours were extracted with various solvents to develop a rapid procedure to isolate glutenin for reversed-phase HPLC (RP-HPLC). Solvents containing 70% ethanol, 60% acetonitrile, 2M dimethylformamide, urea or combinations of 70% ethanol with acetic acid and β-mercaptoethanol did not extract all albumins, globulins and/or gliadins. Some of these proteins may co-elute ...
Handle:
10113/24226

9. A High-Performance Liquid Chromatography Method for Determination of 4-Aminopyridine in Tissues and Urine

Author:
Stan W. Casteel; Brian R. Thomas
Source:
Journal of veterinary diagnostic investigation v.2 no.2 pp. 132-134
ISSN:
1040-6387
Subject:
4-aminopyridine; acetonitrile; aqueous solutions; high performance liquid chromatography; kidneys; liver; methylene chloride; pH; phosphoric acid; poisoning; rats; sodium phosphate; solvents; stomach; tetramethylammonium compounds; urine
Abstract:
... An analytical method was developed to measure 4-aminopyridine in tissues and urine to determine appropriate diagnostic samples in acute poisoning cases. Tissues from rats dosed with 4-aminopyridine were extracted with methylene chloride. Extracts were analyzed by high-performance liquid chromatography using an isocratic solvent system of acetonitrile and aqueous solution (15/85 v/v) consisting of ...
DOI:
10.1177/104063879000200210

10. Acetonitrile and Acrylonitrile Sorption on Montmorillonite from Binary and Ternary Aqueous Solutions

Author:
Z. Z. Zhang; D. L. Sparks; N. C. Scrivner
Source:
Soil Science Society of America journal 1990 v.54 no.6 pp. 1564-1571
ISSN:
0361-5995
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; acetonitrile; aqueous solutions; calcium; carbon 14; clay; magnesium; montmorillonite; organic matter; potassium; sodium; sorption; spectrometers; tracer techniques
Abstract:
... The main objective of this study was to gain mechanistic information on clay-organic interactions in aqueous environments containing multiple organics. Three different measurements were made to achieve this objective. The sorption of acetonitrile and acrylonitrile on K, Na, Ca, and Mg montmorillonite from binary and ternary aqueous solutions were determined using a ¹⁴C isotope tracer method. The i ...
DOI:
10.2136/sssaj1990.03615995005400060009x

11. Sorption and Desorption of Acetonitrile on Montmorillonite from Aqueous Solutions

Author:
Z. Z. Zhang; D. L. Sparks; R. A. Pease
Source:
Soil Science Society of America journal 1990 v.54 no.2 pp. 351-356
ISSN:
0361-5995
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; acetonitrile; aqueous solutions; calcium; carbon 14; clay; desorption; endothermy; heat production; isotope labeling; magnesium; montmorillonite; organic matter; potassium; sodium; sorption; sorption isotherms
Abstract:
... The sorption and desorption of acetonitrile on K, Na, Ca, and Mg montmorillonite from aqueous solutions were determined using a ¹⁴C isotope tracer method. The heat of sorption of acetonitrile on K, Na, and Ca montmorillonite at two concentrations was determined using a Calvet microcalorimeter. The infrared spectra of the clay-water-organic systems were recorded on a Fourier-transform infrared spec ...
DOI:
10.2136/sssaj1990.03615995005400020009x

12. 3,5-Diphenyl-1,2-dithiolium-hydrogensulfat – Bildung und Struktur / 3,5-Diphenyl-1,2-dithiolium Hydrogensulphate – Synthesis and Structure

Author:
Erhard Uhlemann,; Frank Weller
Source:
Zeitschrift für Naturforschung 1992 v.47 no.11 pp. 1501-1504
ISSN:
1865-7117
Subject:
X-radiation; acetonitrile; chlorides; hydrogen bonding; ions; organochlorine compounds
Abstract:
... 3,5-Diphenyl-1,2-dithiolium hydrogensulphate was prepared by the reaction of bis(thiodibenzoylmethanato)-nickel(II) with thionyl chloride in acetonitrile solution. The compound was characterized by X-ray structure determination (1261 observed, independent reflexions, R = 0,056). Crystal data: a = 543,1(1), b = 1605,7(1), c = 1678,9(2) pm; space group P 2₁2₁2₁, Z = 4. By hydrogen bonding the hydrog ...
DOI:
10.1515/znb-1992-1102

13. A Rapid, Sensitive Thin Layer Chromatography Procedure for the Detection of Fumonisin B₁ and B₂

Author:
George E. Rottinghaus; Charles E. Coatney; Harry C. Minor
Source:
Journal of veterinary diagnostic investigation v.4 no.3 pp. 326-329
ISSN:
1040-6387
Subject:
acetonitrile; amino alcohols; corn; detection limit; feeds; fluorescence; fumonisin B1; methanol; potassium chloride; sodium borate; spraying; surveys; thin layer chromatography; ultraviolet radiation; Missouri
Abstract:
... A thin layer chromatography (TLC) method was developed for the detection of fumonisin B₁ and B₂ in corn and corn-based feedstuffs. Finely ground samples were extracted with acetonitrile: water (1: 1), filtered, and applied to C₁₈ cleanup columns. The columns were washed with 1% aqueous KCl followed by acetonitrile: 1% aqueous KC1 (1:9), and the fumonisins were eluted with acetonitrile: water (7:3) ...
DOI:
10.1177/104063879200400316

14. Die Kristallstrukturen der Palladium(II)-Komplexe [Pd(CH₃CN)₄](BF₄)₂, [PdCl(μ₂ -PPh₂)(HPPh₂)]₂ · CH₂Cl₂ und [PdCl(HPPh₂) {H(OPPh₂)₂}] / The Crystal Structures of the Palladium(II) Complexes [Pd(CH₃CN)₄](BF₄)₂, [PdCl(μ₂-PPh₂)(HPPh₂)] · CH₂Cl₂, and [PdCl(HPPh₂){H(OPPh₂)₂}]

Author:
Thorsten Gebauer; Gerlinde Frenzen; Kurt Dehnicke
Source:
Zeitschrift für Naturforschung 1992 v.47 no.11 pp. 1505-1512
ISSN:
1865-7117
Subject:
acetonitrile; anions; chemical bonding; chlorine; crystal structure; ligands; methylene chloride; palladium; phosphorus
Abstract:
... The crystal structures of the title compounds were solved by X-ray methods. [Pd(CH₃CN)4](BF₄)₂: Space group Pbca, Z = 4,812 observed unique reflections, R = 0.057, wR = 0.033. Lattice dimensions at -80 °C: α = 1027.5(5), b = 1242.8(6), c = 1280.3(6) pm. The compound consists of planar [Pd(CH₃CN)4]²⁺ ions with Pd-N bond lengths of 195.6 pm and BF₄⁻ anions. [PdCl(μ₂-PPh₂(HPPh₂)]₂ • CH₂Cl₂ crystalliz ...
DOI:
10.1515/znb-1992-1103

15. Synthese und Charakterisierung achtgliedriger Cyclometallaphosphazene von Niob(V) und Titan(IV) sowie cyclischer und acyclischer Verbindungen von Molybdän(VI) mit Perfluoralkyl-Gruppen – Kristallstruktur von [Ph₂PNONbCl₃]₂ · 4 MeCN / Synthesis and Characterization of Eight-Membered Dimetallacyclophosphazenes with Niobium(V) and Titanium(IV) and Cyclic as well as Acyclic Compounds of Molybdenum(VI) Containing Perfluoroalkyl-Groups – X-Ray Crystal Structure of [Ph₂PNONbCl₃]₂·4MeCN

Author:
Petra Olms; Herbert W. Roesky; Klaus Keller; Mathias Noltemeyer
Source:
Zeitschrift für Naturforschung 1992 v.47 no.11 pp. 1609-1613
ISSN:
1865-7117
Subject:
X-radiation; acetonitrile; crystal structure; crystallization; moieties; molybdenum; niobium; titanium
Abstract:
... Me₃SiOPPh₂NSiMe₃ (1) reacts with NbCl₅ and CpTiCl₃ to form the eight-membered ring compounds [Ph₂PNONbCl₃]₂ (2) and [Ph₂PNOTiClCp]₂ (3). The reaction of (C₂F₅)₂P(Cl)=NSiMe₃ (4) with MoO₂Cl₂ and MoOCl₄ in CH₂C1₂ quantitatively yields the compounds [MoOCl₃-O-P(C₂F₅)₂=NSiMe₃]₄ (5) and (C₂F₅)₂P(Cl)=N-MoOCl₃ (6). Through recrystallization from MeCN, compound 2 has been isolated and characterized by mea ...
DOI:
10.1515/znb-1992-1115

16. [Mn(SPh)₃Cl]²-, [Mn(SPh)₃Br]²⁻, [Mn(SePh)₄]²⁻, [Mn(TePh)₄]²⁻, and [Co₄(SPh)₆Cl₄]²⁻: New Mixed Halide/Thiolate and Chalcogenolate Complexes of Manganese and Cobalt

Author:
Wolfgang Tremel; Bernt Krebs; Klaus Greiwe; Wolfgang Simon; Hans-Oscar Stephan; Gerald Henkel
Source:
Zeitschrift für Naturforschung 1992 v.47 no.11 pp. 1580-1592
ISSN:
1865-7117
Subject:
acetonitrile; anions; bromine; chlorine; cobalt; crystals; iron; ligands; manganese; methanol; nuclear magnetic resonance spectroscopy; physical properties; stereochemistry; tetraethylammonium compounds
Abstract:
... The reactions of 1:1:1 molar ratio mixtures of NaSPh/MnCl₂/Et₄NBr and NaSPh/CoCl₂/ Et₄NCl in methanol afford the compounds [Et₄N]₄[Mn(SPh)₃Br][Mn(SPh)₃Cl] (1) and [Et₄N]₂[Co₄(SPh)₆Cl₄] · MeCN (2), respectively, with the following crystal data: a = 14.408(5), b = 13.788(4), c = 17.984(5) Å, β = 90.16(2)°, space group P2₁/c and Ζ = 4 for 1, and a = 21.976(4), b = 13.081(2), c = 22.012(4) Å, β = 105. ...
DOI:
10.1515/znb-1992-1112

17. Interest of pulsed electrochemical detection for the analysis of flavor-active alcohols separated by liquid chromatography

Author:
Le Fur, E.; Etievant, P.X.; Meunier, J.M.
Source:
Journal of agricultural and food chemistry 1994 v.42 no.2 pp. 320-326
ISSN:
0021-8561
Subject:
flavor compounds; alcohols; chemical analysis; separation; solvents; nitriles; redox potential
Abstract:
... Electrochemical detection of short-chain aliphatic alcohols separated by liquid chromatography demonstrates close sensitivities at gold and platinum working electrodes. Addition of acetonitrile in the eluent decreases the sensitivity of detection peak area) at the gold electrode but improves the apparent sensitivity (peak height) by a consequent decrease of retention time. At the platinum electrod ...
DOI:
10.1021/jf00038a017

18. Stability of fumonisins (FB1 and FB2) in solution

Author:
Visconti, A.; Doko, M.B.; Bottalico, C.; Schurer, B.; Boenke, A.
Source:
Food additives & contaminants 1994 v.11 no.4 pp. 427-431
ISSN:
0265-203X
Subject:
mycotoxins; solutions; degradation; methanol; nitrites; reference standards
Abstract:
... The stability of fumonisins B1 and B2 (FB1 and FB2) during 6 week storage was studied in acetonitrile:water (1:1) and methanol at four storage temperatures (-18, 4, 25 and 40 degrees C). Samples were analysed by HPLC with fluorescence detection after derivatization with o-phthaldialdehyde. Decomposition of fumonisins was evident in a methanol solution after 6 week storage at 4, 25 and 40 degrees C ...
DOI:
10.1080/02652039409374244
PubMed:
7958112

19. Prion protein peptides induce alpha-helix to beta-sheet conformational transitions

Author:
Nguyen, J.; Baldwin, M.A.; Cohen, F.E.; Prusiner, S.B.
Source:
Biochemistry 1995 v.34 no.13 pp. 4186-4192
ISSN:
0006-2960
Subject:
Fourier transform infrared spectroscopy; Mesocricetus auratus; PrPSc proteins; acetonitrile; buffers; cell structures; circular dichroism spectroscopy; mice; models; molybdenum; physical properties; synthetic peptides
Abstract:
... The structures of synthetic peptides corresponding to regions of putative secondary structure in the cellular prion protein PrPC were studied as models for the conformational transition that features in the formation of the pathogenic isoform, PrPSc. Transgenetic studies argue that these PrP isoforms interact during the formation of PrPSc, which involves the unfolding of one or more helices of PrP ...
DOI:
10.1021/bi00013a006
PubMed:
7703230

20. Adsorption and Desorption of Nicosulfuron in Soils

Author:
Javier M. Gonzalez; Ljerka Ukrainczyk
Source:
Journal of environmental quality 1996 v.25 no.6 pp. 1186-1192
ISSN:
0047-2425
Subject:
calcium chloride; kaolinite; Zea mays; clay fraction; weed control; iron oxides; nicosulfuron; acetonitrile; clay; corn; aluminum; hysteresis; pH; sorption isotherms; groundwater; desorption; adsorption; Iowa
Abstract:
... Nicosulfuron (2-[[[[(4,6-dimethoxy-2-pyrimidinyl)amino]carbonyl]amino]sulfonyl]-N,N-dimethyl-3-pyridinecarboxamide) is a new, low-rate, sulfonylurea herbicide that is being promoted for weed control in corn (Zea mays L.); however, there is a lack of published information on its behavior in soils. In this study nicosulfuron sorption was measured in batch experiments, at a 1:2 soil/solution ratio, f ...
DOI:
10.2134/jeq1996.00472425002500060003x

21. Aerobic biodegradation of (14C)-sarafloxacin hydrochloride in soil

Author:
Marengo, J.R.; Kok, R.A.; O'Brien, K.; Velagaleti, R.R.; Stamm, J.M.
Source:
Environmental toxicology and chemistry 1997 v.16 no.3 pp. 462-471
ISSN:
0730-7268
Subject:
acetonitrile; acid hydrolysis; antibiotics; biodegradation; high performance liquid chromatography; mineralization; organic matter; potassium hydroxide; poultry diseases; sand; sandy loam soils; sarafloxacin; silt; solvents
Abstract:
... The aerobic biodegradation of sarafloxacin hydrochloride, a fluoroquinolone antibiotic registered for use against poultry diseases, was tested in three soils: loam, silt loam, and sandy loam. Sarafloxacin treatment demonstrated mineralization to 14CO2 amounting to 0.58%, 0.49%, and 0.57% in loam, silt loam, and sandy loam soils, respectively, at the termination of the test. The extractability of s ...
DOI:
10.1897/1551-5028(1997)016<0462:ABOCSH>2.3.CO;2

22. Application of empore disk extraction for trace analysis of spinosad and metabolites in leafy vegetables, peppers, and tomatoes by high-performance liquid chromatography with ultraviolet detection

Author:
Yeh, L.T.; Schwedler, D.A.; Schelle, G.E.; Balcer, J.L.
Source:
Journal of agricultural and food chemistry 1997 v.45 no.5 pp. 1746-1751
ISSN:
0021-8561
Subject:
acetonitrile; cabbage; liquid-liquid extraction; mass spectrometry; metabolites; peppers; reversed-phase high performance liquid chromatography; silica; solid phase extraction; spinosad; tomatoes
Abstract:
... Residue methods were developed for the quantitation of spinosad and metabolites in leafy vegetables, peppers, and tomatoes. The compounds were extracted with a solution of acetonitrile/water. The extract was purified and concentrated by C18 Empore disk extraction, followed by silica and cyclohexyl solid-phase extraction. All five analytes in the purified extract were determined simultaneously by r ...
DOI:
10.1021/jf960579d

23. Detection of two naturally occurring structural isomers of partially hydrolyzed fumonisin B1 in corn by on-line capillary liquid chromatography-fast atom bombardment mass spectrometry

Author:
Xie, W.; Mirocha, C.J.; Chen, J.
Source:
Journal of agricultural and food chemistry 1997 v.45 no.4 pp. 1251-1255
ISSN:
0021-8561
Subject:
acetonitrile; cleaning; corn; fumonisin B1; fumonisin B2; hydrolysis; isomers; liquid chromatography; mass spectrometry; screening; seeds; solid phase extraction
Abstract:
... Fifteen corn kernel and corn screening samples were analyzed for the presence of fumonisin toxins. Samples were extracted with acetonitrile/water (1:1) and cleaned up with C18 solid phase extraction (SPE) cartridges. Analysis of fumonisins was carried out by on-line capillary liquid chromatography -- fast atom bombardment mass spectrometry (capillary LC/FAB/MS). Two isomers of partially hydrolyzed ...
DOI:
10.1021/jf960482r

24. Determination of caffeine in tea products by an improved high-performance liquid chromatography method

Author:
Naik, J.P.; Nagalakshmi, S.
Source:
Journal of agricultural and food chemistry 1997 v.45 no.10 pp. 3973-3975
ISSN:
0021-8561
Subject:
acetonitrile; black tea; caffeine; high performance liquid chromatography; pigments; tea (beverage)
Abstract:
... At present, the commonly used HPLC method for the analysis of caffeine content in tea brews employs direct application of the samples on the column. This practice gradually reduces the efficiency of the column and shortens its life. In the modified method, the interfering tea pigments are effectively removed by passing the sample through a Sep-Pak C18 cartridge. Then its injection on a reversed ph ...
DOI:
10.1021/jf970147i

25. Determination of formaldehyde and acetaldehyde in air by HPLC with fluorescence detection

Author:
M. Possanzini; V. Di Palo
Source:
Chromatographia 1997 v.46 no.5-6 pp. 235-240
ISSN:
0009-5893
Subject:
acetaldehyde; acetonitrile; air; detection limit; fluorescence; fluorometry; formaldehyde; ozone; reversed-phase high performance liquid chromatography; silica gel; storage quality
Abstract:
... Sensitive detection of atmospheric formaldehyde and acetaldehyde can be achieved by use of silica-gel cartridges impregnated with 2-diphenylacetyl-1,3-indandione-1-hydrazone (DAIH) to form fluorescent DAI hydrazones. The hydrazones are extracted with acetonitrile and separated by reversed-phase HPLC with fluorimetric detection. The low detection limits achieved (0.25 ppb CH₂O or CH₃CHO for samplin ...
DOI:
10.1007/BF02496312

26. Determination of organophosphorus pesticides and metabolites in crops by solid-phase extraction followed by liquid chromatography/Diode array detection

Author:
A. Laganà; G. D'Ascenzo; G. Fago; A. Marino
Source:
Chromatographia 1997 v.46 no.5-6 pp. 256-264
ISSN:
0009-5893
Subject:
acetone; acetonitrile; adsorption; cleaning; crops; cultivars; liquid chromatography; malaoxon; metabolites; methanol; multiresidue analysis; quantitative analysis; solid phase extraction; solvents
Abstract:
... A multiresidue method for the analysis of 28 common organophosphorus pesticides and 3 of their main metabolites (paraoxon-ethyl, paraoxon-methyl and malaoxon) in a variety of crop samples has been developed. An aliquot of the chopped sample is homogenized with an organic solvent. The efficiency of extraction methods using methanol, acetone and acetonitrile was evaluated. The acetonitrile gives hig ...
DOI:
10.1007/BF02496316

27. Diuron and its metabolites in surface water and ground water by solid phase extraction and in-vial elution

Author:
Field, J.A.; Reed, R.L.; Sawyer, T.E.; Martinez, M.
Source:
Journal of agricultural and food chemistry 1997 v.45 no.10 pp. 3897-3902
ISSN:
0021-8561
Subject:
acetonitrile; diuron; field experimentation; groundwater; high performance liquid chromatography; metabolites; methanol; rapid methods; solid phase extraction; surface water
Abstract:
... A simple and rapid method was developed to determine concentrations of diuron [N'-(3,4-dichlorophenyl)-N,N-dimethylurea] and three of its major metabolites, N'-(3,4-dichlorophenyl)-N-methylurea (DCPMU), 3,4-dichlorophenylurea (DCPU), and 3,4-dichloroaniline (DCA), in ground water and surface water. The analytical method utilizes a 25 mm C18 Empore disk to quantitatively determine diuron and its me ...
DOI:
10.1021/jf970196v

28. Effect of application solvents on heterotrophic and nitrifying populations in soil microcosms

Author:
Miller, J.L.; Sardo, M.A.; Thompson, T.L.; Miller, R.M.
Source:
Environmental toxicology and chemistry 1997 v.16 no.3 pp. 447-451
ISSN:
0730-7268
Subject:
acetonitrile; air; ammonia; carbon; fuels; groundwater; methanol; methylene chloride; mineralization; naphthalene; nitrification; nitrogen fertilizers; pesticides; soil; soil ecology; soil pollution; solvents
Abstract:
... Agricultural practices may cause contamination of soil and ground water with a combination of organic compounds (pesticides and fuel) and nitrogen fertilizers. In coupled microcosm studies that monitored the mineralization of naphthalene and the nitrification of ammonia, it was observed that the solvent (dichloromethane) used to apply naphthalene to the soil inhibited nitrification, although there ...
DOI:
10.1897/1551-5028(1997)016<0447:EOASOH>2.3.CO;2

29. HPLC-fluorescence method for the determination of eprinomectin marker residue in edible bovine tissue

Author:
Payne, L.D.; Mayo, V.R.; Morneweck, L.A.; Hicks, M.B.; Wehner, T.A.
Source:
Journal of agricultural and food chemistry 1997 v.45 no.9 pp. 3501-3506
ISSN:
0021-8561
Subject:
acetonitrile; cattle; detection limit; eprinomectin; fluorescence; kidneys; liver; muscles; rapid methods; sodium sulfate; solvents
Abstract:
... A method was developed and validated to determine eprinomectin marker residue in bovine liver, kidney, muscle, and fat. The overall percent recovery (+/- CV) was 93 +/- 12% (n = 66) for liver, 100 +/- 13% (n = 34) for muscle, 87 +/- 13% (n = 42) for kidney, and 95 +/- 11% (n = 42) for fat. The limit of detection was 1 ng/g, the lower limit of quantitation was 2 ng/g, and the upper limit of quantit ...
DOI:
10.1021/jf970393u

30. Lipase-catalyzed Synthesis of Arbutin Cinnamate in an Organic Solvent and Application of Transesterification to Stabilize Plant Pigments

Author:
Nobuyoshi Nakajima; Kohji Ishihara; Shingo Matsumura; Hiroki Hamada; Kaoru Nakamura; Tsutomu Furuya
Source:
Bioscience, biotechnology, and biochemistry 1997 v.61 no.11 pp. 1926-1928
ISSN:
1347-6947
Subject:
acetonitrile; alcohols; biotechnology; callistephin; carboxylic ester hydrolases; cinnamic acid; glucose; isoquercitrin; moieties; pelargonidin; quercetin; regioselectivity; solvents; transesterification
Abstract:
... Arbutin cinnamate was synthesized from arbutin (4-hydroxy-phenyl β-D-glucopyranoside) and vinyl cinnamate by regioselective transesterification with a bacterial lipase in acetonitrile. The product was identified by NMR and FAB-MS analyses. These spectra showed that one ester bond was formed between the primary alcohol moiety of the D-glucose of arbutin and the carboxyl residue of cinnamic acid. Fu ...
DOI:
10.1271/bbb.61.1926

31. Method for the determination of veratridine and cevadine, major components of the natural insecticide sabadilla, in lettuce and cucumbers

Author:
Zang, X.J.; Fukuda, E.K.; Rosen, J.D.
Source:
Journal of agricultural and food chemistry 1997 v.45 no.5 pp. 1758-1761
ISSN:
0021-8561
Subject:
acetonitrile; atmospheric pressure; cleaning; cucumbers; detection limit; farmers; high performance liquid chromatography; insecticides; ionization; lettuce; mass spectrometry; monitoring; solid phase extraction
Abstract:
... Sabadilla, an insecticide widely used by organic farmers, can be separated into five of its components (veratridine, cevadine, cevine, cevacine, and sabadine) by high-performance liquid chromatography (HPLC) and detected by atmospheric pressure chemical ionization liquid chromatography mass spectrometry (APCI/LCMS). Using APCI/LCMS in the selected ion monitoring mode as the determinative step, an ...
DOI:
10.1021/jf9606013

32. Quantitative recovery of sulfonamides from chicken liver, beef liver, and egg yolk via modified supercritical carbon dioxide

Author:
Combs, M.T.; Boyd, S.; Ashraf-Khorassani, M.; Taylor, L.T.
Source:
Journal of agricultural and food chemistry 1997 v.45 no.5 pp. 1779-1783
ISSN:
0021-8561
Subject:
acetone; acetonitrile; beef; carbon dioxide; chickens; chromatography; egg yolk; ethanol; liver; methanol; quantitative analysis; sulfadimethoxine; sulfaquinoxaline
Abstract:
... Solutions of supercritical CO2 modified with 5, 10, and 20% methanol, ethanol, acetone, and acetonitrile were compared for the extraction of sulfonamides from fortified chicken liver. The results showed both 20% acetone-modified CO2 and 20% acetonitrile-modified CO2 were capable of quantitatively extracting sulfamethazine, sulfaquinoxaline, and sulfadimethoxine, whereas 20% ethanol- and 20% methan ...
DOI:
10.1021/jf960814s

33. A covalent two-step immobilization technique using itaconic anhydride

Author:
Fischer, L.; Peissker, F.
Source:
Applied microbiology and biotechnology 1998 v.49 no.2 pp. 129-135
ISSN:
0175-7598
Subject:
acetonitrile; acrylamides; almonds; amino acids; beta-glucosidase; chloramphenicol; derivatization; storage quality; sulfhydryl groups
Abstract:
... beta-Glucosidase from almonds (EC 3.2.1.21) was covalently immobilized by a two-step technique. In the first step, double bonds were introduced into the beta-glucosidase by derivatization with itaconic anhydride. In separate studies with alpha-N-protected L-amino acids, it was established that itaconic anhydride acylated mainly primary amino groups of lysines and, to a much lesser extent hydroxyl ...
DOI:
10.1007/s002530051148

34. Determination of aloesin in plasma by high-performance liquid chromatography as fluorescent 9-anthroyl derivative

Author:
Kyeong Ho Kim; Jin Gyun Lee; Jeong Hill Park; Young Geun Shin; Seung Ki Lee; Tae Hyung Cho; Sun Tack Oh
Source:
Archives of pharmacal research 1998 v.21 no.6 pp. 651
ISSN:
0253-6269
Subject:
acetonitrile; derivatization; detection limit; fluorescence; high performance liquid chromatography; methanol; solid phase extraction
Abstract:
... A sensitive high-performance liquid chromatographic (HPLC) method for the determination of aloesin in plasma was developed. After solid-phase extraction from plasma and derivatization of aloesin and compound AD-1, which was prepared from aloesin as a internal standard, with 9-anthroylnitrile in the presence of quinuclidine, the derivatives were separated on a Inertsil ODS-3 column using acetonitri ...
DOI:
10.1007/BF02976752

35. Determination of two metabolites of albendazole, albendazole-sulfoxide and albendazole-sulfone in cow's milk using an HPLC method —A systematic approach to optimise extraction conditions

Author:
Zs. Romvári; J. Fekete; S. Kemény; G. Pokol; I. Gebefügi; A. Kettrup
Source:
Chromatographia 1998 v.48 no.11-12 pp. 777-784
ISSN:
0009-5893
Subject:
acetonitrile; albendazole; detection limit; humans; metabolites; methanol; milk; phosphates; reversed-phase high performance liquid chromatography
Abstract:
... Reversed phase HPLC methods for the determination of two metabolites of albendazole in cow's milk are described. Albendazole is an anthelmintic agent used both in veterinary and human practice. Its main metabolites are albendazole-sulfoxide and albendazole-sulfone. The separation of the two metabolites was performed on a μ-Bondapak C-18 column using an acetonitrile/methanol/phosphate buffer as mob ...
DOI:
10.1007/BF02467647

36. Development and validation of stability indicating high-performance liquid chromatographic assays for ketotifen in aqueous and silicon oil formulations

Author:
I. P. Nnane; L. A. Damani; A. J. Hutt
Source:
Chromatographia 1998 v.48 no.11-12 pp. 797-802
ISSN:
0009-5893
Subject:
absorption; acetonitrile; aqueous solutions; correlation; high performance liquid chromatography; hydrochloric acid; oils; oxidative stress; pH; phosphates; silicon; trimethylamine; ultraviolet radiation
Abstract:
... A simple and specific high-performance liquid chromatographic (HPLC) method for the analysis of ketotifen in aqueous solutions and silicon oil suspensions is described. The HPLC system is based on a reversed phase μBondapak C₁₈ (30×0.39 cm) column with a mobile phase of phosphate buffer (0.001 M, pH 7.4):methanol: acetonitrile: trimethylamine (29.8:45:25:0.2, by volume) at a flow-rate of 1 mL min⁻ ...
DOI:
10.1007/BF02467650

37. HPLC Analysis of Anomeric Formation and Cleavage Pattern by Chitinolytic Enzyme

Author:
Daizo KOGA; Takanori YOSHIOKA; Yasuyuki ARAKANE
Source:
Bioscience, biotechnology, and biochemistry 1998 v.62 no.8 pp. 1643-1646
ISSN:
1347-6947
Subject:
acetonitrile; biotechnology; enzymes; reaction mechanisms
Abstract:
... The reactions of N-acetylchitooligosaccharides with chitinolytic enzyme were analyzed by HPLC using a Tosoh TSK-Gel amide-80 column with 70% acetonitrile as an eluent. We separated α and β anomeric forms of N-acetylchitooligosaccharides, and obtain the following advantages of this HPLC method. 1. We can easily identify the reaction mechanism of chitinolytic enzymes by this method, distinguishing t ...
DOI:
10.1271/bbb.62.1643

38. Kristallstruktur des Oxo-Acetatkomplexes [Co₇(μ₄- O)₂(O₂CCH₃)₁₀(OPEt₃)₂] / Crystal Structure of the Oxo-Acetate Complex [Co₇(μ₄ -O)₂(O₂CCH₃)10(OPEt₃)₂]

Author:
Hartmut Ackermann; Roland Leo; Werner Massa; Kurt Dehnicke
Source:
Zeitschrift für Naturforschung 1998 v.53 no.10 pp. 1241-1243
ISSN:
1865-7117
Subject:
acetates; acetonitrile; cobalt; crystal structure; crystallization; crystals
Abstract:
... Cobalt(II)acetate reacts with the silylated phosphinimine Me₃SiNPEt₃ at 230 °C to form a reaction mixture from which dark blue single crystals have been isolated by recrystallization from dichloromethane/ acetonitrile. They were identified by a crystal structure determination to be [Co₇(μ₄- O)₂(O₂CCH₃)₁₀(OPEt₃)₂] · 4 CH₃CN (1). Lattice dimensions at 190 K: a = 1048.9(1), b = 1217.5(1), c = 1280.6( ...
DOI:
10.1515/znb-1998-1023

39. Photochemical Reductive Elimination of Nitrogen from Triazidogallium(III). Generation of Luminescent Gallium(I)

Author:
Horst Kunkely; Arnd Vogler
Source:
Zeitschrift für Naturforschung 1998 v.53 no.10 pp. 1180-1182
ISSN:
1865-7117
Subject:
absorption; acetonitrile; equations; gallium; irradiation; luminescence; nitrogen; photochemistry
Abstract:
... The irradiation of Ga(N₃)₃ in CH₃CN leads to a reductive elimination of nitrogen according to the equation Gaᴵᴵᴵ(N₃)₃ → GaᴵN₃ + 3N₂ (φ = 0.002 at λᵢᵣᵣ = 254 nm). Ga⁺ in CH₃CN is characterized by its absorption (λₘₐₓ = 298 nm) and emission (λₘₐₓ = 475 nm) spectrum ...
DOI:
10.1515/znb-1998-1012

40. Resolution of salbutamol enantiomers in human urine by reversed-phase high performance liquid chromatography after derivatization with 2,3,4,6-tetra-O-acetyl-β-D-glycopyranosyl isothiocyanate

Author:
Kyeong Ho Kim; Tae Kyun Kim
Source:
Archives of pharmacal research 1998 v.21 no.2 pp. 217-222
ISSN:
0253-6269
Subject:
acetonitrile; ammonium acetate; derivatization; detection limit; electrochemistry; enantiomers; humans; reversed-phase high performance liquid chromatography; solid phase extraction; urine
Abstract:
... A stereospecific HPLC method has been developed for the resolution of the enantiomers of salbutamol in human urine. After solid-phase extraction and derivatization with 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate, the diastereomeric derivatives were resolved (Rs=1. 83) on 5 μm octadecylsilan column using 35% acetonitrile in 0.05M ammonium acetate buffer (pH=6) as a mobile phase with e ...
DOI:
10.1007/BF02974031

41. Acetonitrile-hydrolysing enzymes in Rhodococcus erythropolis A10

Author:
A. Acharya; A.J. Desai
Source:
World journal of microbiology & biotechnology 1999 v.15 no.1 pp. 111-113
ISSN:
0959-3993
Subject:
Rhodococcus erythropolis; acetonitrile; amidase; ammonium sulfate; cobalt; glucose; iron
Abstract:
... Rhodococcus erythropolis A10 metabolizes acetonitrile by a two step process involving nitrile hydratase (NHase) and amidase. Both the enzymes were inducible and low basal levels of activities were observed in the cells grown in the absence of acetonitrile (AN). Cobalt and iron enhanced NHase, while amidase showed iron dependence. Presence of glucose or ammonium sulphate (AS) failed to affect aceto ...
DOI:
10.1023/A:1008821412284

42. Activation of serine protease subtilisin Carlsberg in organic solvents: combined effect of methyl-β-cyclodextrin and water

Author:
Angélica M. Santos; Ileana Montañez Clemente; Gabriel Barletta; Kai Griebenow
Source:
Biotechnology letters 1999 v.21 no.12 pp. 1113-1118
ISSN:
0141-5492
Subject:
acetonitrile; beta-cyclodextrin; enantiomers; freeze drying; solvents; subtilisin; transesterification
Abstract:
... Methyl β-cyclodextrin (MβCD) increased the activity and enantioselectivity of lyophilized subtilisin suspended in dry THF and acetonitrile in two transesterification model reactions. These beneficial improvements were diminished by the addition of water, in contrast to the observation that water activates subtilisin lyophilized from buffer alone. For example, the initial rate for the S enantiomer ...
DOI:
10.1023/A:1005626211015

43. An improved method for the determination of sulphachloropyrazine in meat and liver of broilers during and after their treatment for coccidiosis

Author:
Lj. Kostadinovic; S. Pavkov; F. Gaál
Source:
Acta alimentaria 1999 v.28 no.4 pp. 311-319
ISSN:
0139-3006
Subject:
acetonitrile; ammonia; aqueous solutions; broiler chickens; coccidiosis; coccidiostats; drugs; high performance liquid chromatography; liver; meat; methylene chloride; muscle tissues; quantitative analysis; solvents
Abstract:
... The paper presents results of the HPLC determination of sulphachloropyrazine residues (active component of the drug „Esb3 30%”) in muscle tissue and liver of broiler chickens inoculated with laboratory-grown coccidium in the course and after treatment with this sulphonamide.Extraction of sulphachloropyrazine from samples of broiler muscle tissue and liver was carried out with a mixture of solvents ...
DOI:
10.1556/AAlim.28.1999.4.2

44. Automated high-performance liquid chromatographic determination of amphetamine in biological fluids using column-switching and on-column derivatization

Author:
R. Herráez-Hernández; P. Campíns-Falcó; S. Díaz-Oltra
Source:
Chromatographia 1999 v.49 no.3-4 pp. 188-196
ISSN:
0009-5893
Subject:
acetonitrile; amphetamine; derivatization; detection limit; fluorescence; liquid chromatography; urine
Abstract:
... A rapid and simple liquid-chromatographic method has been developed for on-line quantification of amphetamine in biological fluids. Untreated samples (20 μL) are injected directly into the chromatographic system and purified on a 20 mm×2.1 mm i.d. pre-column packed with 30 μm Hypersil C₁₈ stationary phase. After clean-up the analyte is transferred to the analytical column (125 mm×4 mm i.d., 5 μm L ...
DOI:
10.1007/BF02575284

45. Chromatographic separation and analysis of chloropheniramine maleate, methscopolamine nitrate and phenylephrine hydrochloride in sustained release capsules

Author:
M. E-S. Metwally
Source:
Chromatographia 1999 v.50 no.1-2 pp. 113-117
ISSN:
0009-5893
Subject:
acetic acid; acetonitrile; liquid chromatography; maleates; nitrates; phenylephrine; sodium
Abstract:
... A high performance liquid chromatographic method has been developed for the simultaneous determination of chlorpheniramine maleate (CPM), methscoplamine nitrate (MSN) and phenylephrine hydrochloride (PEH) in sustained release capsules. The separation was carried out on a reverse-phase CN-column with use of a mobile phase consisting of 70% (v/v) solution of acetonitrile in water containing 2% (v/v) ...
DOI:
10.1007/BF02493628

46. Determination of biogenic amines in fermented beverages and vinegars by pre-column derivatization withpara-nitrobenzyloxycarbonyl chloride (PNZ-Cl) and reversed-phase LC

Author:
J. Kirschbaum; A. Meier; H. Brückner
Source:
Chromatographia 1999 v.49 no.3-4 pp. 117-124
ISSN:
0009-5893
Subject:
acetonitrile; ambient temperature; beers; cabbage; cadaverine; chromatography; derivatization; detection limit; food matrix; histamine; juices; pH; putrescine; quantitative analysis; serotonin; sodium; sodium acetate; spermidine; spermine; tryptamine; tyramine; vinegars; wines
Abstract:
... The reagentp-nitrobenzyloxycarbonyl chloride (PNZ-CI) was used for pre-column derivatization of biogenic amines (BAs) at ambient temperature followed by reversed-phase, liquid-chromatographic separation of the derivatives. Optimized derivatization of samples was achieved within 10 min in borate buffer by adding PNZ-Cl in acetonitrile (MeCN). Excess reagent was scavenged by subsequent addition of g ...
DOI:
10.1007/BF02575272

47. Investigation of various extractants for the analysis of aflatoxin B1 in different food and feed matrices

Author:
Stroka, J.; Petz, M.; Joerissen, U.; Anklam, E.
Source:
Food additives & contaminants 1999 v.16 no.8 pp. 331-338
ISSN:
0265-203X
Subject:
aflatoxins; paprika; infant formulas; feeds; analytical methods; methanol; acetone; accuracy
Abstract:
... Various extractions were investigated concerning their suitability for aflatoxin B(1) determinations in different matrices including spices, infant formula and animal feed employing an immunoaffinity clean-up procedure. It was shown that the use of aqueous acetonitrile extractants was limited due to the fact that dry sample material can absorb significant amounts of water from the extractant. This ...
DOI:
10.1080/026520399283902
PubMed:
10645347

48. Optimization of an HPLC method for the separation of erythromycin and related compounds using factorial design

Author:
V. Harang; D. Westerlund
Source:
Chromatographia 1999 v.50 no.9-10 pp. 525-531
ISSN:
0009-5893
Subject:
acetonitrile; erythromycin; high performance liquid chromatography; hydrogen; pH; phosphates; sulfates
Abstract:
... An HPLC method based on a prodigy ODS2 column with a mobile phase contianging phosphate buffer, tetrabutylammonium hydrogen sulfate (TBA) and an acetonitrile gradient was optimized for the determination of erythromycin in delayed-release capsules. A central composite face-centered (CCF) factorial design was used with the factors pH, concentration of TBA and gradient slope. The method could separat ...
DOI:
10.1007/BF02493656

49. Quantification of trovafloxacin in serum by high-performance liquid chromatography with on-line solid-phase extraction

Author:
S. Bompadre; L. Ferrante; L. Leone; S. Ripa
Source:
Chromatographia 1999 v.49 no.3-4 pp. 185-187
ISSN:
0009-5893
Subject:
absorbance; acetonitrile; blood serum; correlation; detection limit; drugs; high performance liquid chromatography; humans; ion pair chromatography; solid phase extraction
Abstract:
... A rapid, simple, accurate and sensitive liquid chromatographic assay with on-line solid-phase extraction is described for determination of trovafloxacin in human serum. Samples were deproteinized with acetonitrile and injected on to an NH₂ extraction column for sample clean-up. Thereafter, an on-line column-switching system was used for quantitative transfer of the drug to a C₁₈ analytical column. ...
DOI:
10.1007/BF02575283

50. Reversed-phase high-performance liquid chromatographic separation of32P-labeled nucleotide adducts formed by food-derived carcinogenic aminoimidazoazarenes

Author:
U. Brockstedt; W. Pfau
Source:
Chromatographia 1999 v.50 no.9-10 pp. 547-552
ISSN:
0009-5893
Subject:
DNA adducts; acetonitrile; carcinogenesis; carcinogenicity; carcinogens; chemical bonding; equipment; fish meat; fried meat; genotoxicity; heterocyclic amines; humans; ion exchange; ionic strength; mutagenicity; nucleotides; pH; phosphates; reversed-phase high performance liquid chromatography; silica gel; thin layer chromatography; tissues
Abstract:
... Carcinogenic heterocyclic amines are formed on the surface of grilled or fried meat and fish. These heterocyclic amines have been shown to form the covalent DNA adducts considered to be the first stage of the process of carcinogenesis. In this paper we describe the separation of DNA adducts formed by six food-derived mutagenic aminoimidazoazarenes.³²P-Postlabeling is the most sensitive technique f ...
DOI:
10.1007/BF02493659

51. Separation and identification of chiralN-acylcalix[4]arene amino acid derivatives by use of reversed-phase HPLC

Author:
S. J. Thibodeaux; M. Sañchez Peña; Y. Zhang; S. A. Shamsi; I. M. Warner
Source:
Chromatographia 1999 v.49 no.3-4 pp. 142-146
ISSN:
0009-5893
Subject:
acetonitrile; amino acid derivatives; phosphoric acid; reversed-phase high performance liquid chromatography
Abstract:
... This work focuses on the separation and identification of p-tert butyl calix[4]arene derivatives. An isocratic mixture of 65% (v/v) acetonitrile and 35% (v/v) water with 0.1% (v/v) phosphoric acid was used as the mobile phase. A Bio-Rad Bio-Sil ODS-5S (250 mm×4 mm) column was used as the stationary phase with UV detection of the analytes at 274 nm. The reversed-phase high performance liquid chroma ...
DOI:
10.1007/BF02575276

52. Simultaneous Determination of Different Classes of Lipid Hydroperoxides by High-Performance Liquid Chromatography with Post Column Detection by a Ferrous/Xylenol Orange Reagent

Author:
Keiji SUGINO
Source:
Bioscience, biotechnology, and biochemistry 1999 v.63 no.4 pp. 773-775
ISSN:
1347-6947
Subject:
acetonitrile; biotechnology; cholesterol; high performance liquid chromatography; hydroperoxides; lipid peroxides; methanol; oxidation; phosphatidylcholines; rats; silica; triacylglycerols
Abstract:
... A novel high-performance liquid chromatographic (HPLC) method with post-column detection was developed to simultaneously analyze the lipid hydroperoxides of polar and nonpolar lipids. The HPLC method uses a reversed-phase column (octyl-bonded silica) and a mobile phase of water/acetonitrile/methanol. Hydroperoxides were detected at 592 nm by using a ferrous (II)/xylenol orange (FeXO) reagent. This ...
DOI:
10.1271/bbb.63.773

53. Simultaneous determination of seven sunscreen benzophenones in cosmetic products by high-performance liquid chromatography

Author:
Lai-Hao Wang
Source:
Chromatographia 1999 v.50 no.9-10 pp. 565-570
ISSN:
0009-5893
Subject:
acetonitrile; high performance liquid chromatography; methanol; sunscreens
Abstract:
... A HPLC method for the simultaneous determination of benzophenones is described. The seven compounds studied were separated on a Hypersil ODS C₁₈ (25 cm×4.6 mm i.d.) using acetonitrile-methanol-water (30:30:40,v/v/v) as mobile phase at 1.0 mL min⁻¹ and detected at 286 nm. The results obtained were in good agreement with those obtained by differential pulse voltammetry. ...
DOI:
10.1007/BF02493662

54. Antifungal properties of substituted 1-phenyl-5-mercaptotetrazoles and their oxidation product, 5-bis-(1-phenyltetrazolyl) disulfide

Author:
K. Nesměrák; M. Pospíšek; I. Němec; K. Waisser; J. Gabriel
Source:
Folia microbiologica 2000 v.45 no.2 pp. 138-142
ISSN:
0015-5632
Subject:
Candida; Cryptococcus albidus; Trichosporon cutaneum; acetonitrile; acids; antifungal agents; antifungal properties; electrochemistry; minimum inhibitory concentration; models; oxidation
Abstract:
... The antifungal effect of substituted 1-phenyl-5-mercaptotetrazoles was tested with Candida tropicalis, C. pseudotropicalis, C. mogii, Trichosporon cutaneum, Cryptococcus albidus and S. cerevisiae. Candida strains exhibited the lowest sensitivity to the compounds; the most sensitive wasS. cerevisiae. The MIC values ranged from 40 to >1000 mg/mL. The antifungal effect of halogenated compounds decrea ...
DOI:
10.1007/BF02817412

55. Automated flow system on-line to LC with postcolumn derivatisation for determination of sugars in carbohydrate-rich foods

Author:
A. Cáceres; S. Cárdenas; M. Gallego; A. Rodríguez; M. Valcárcel
Source:
Chromatographia 2000 v.52 no.5-6 pp. 314-318
ISSN:
0009-5893
Subject:
acetonitrile; activated carbon; chromatography; decolorization; derivatization; dried milk; fructose; lactose; maltose; maltotriose; nonreducing sugars; p-aminobenzoic acid; reducing sugars; sucrose
Abstract:
... A method for the direct determination of carbohydrates in foods using an automated-flow system coupled on-line to a high-performance liquid chromatograph is proposed. The method is based on postcolumn derivatisation of reducing sugars with p-aminobenzoic acid hydrazide in an alkaline medium following elution from the chromatographic column with an acetonitrile: water gradient as mobile phase. The ...
DOI:
10.1007/BF02491024

56. Biophysical studies of the development of amyloid fibrils from a peptide fragment of cold shock protein B

Author:
Deborah K. Wilkins; Christopher M. Dobson; Michael Groß
Source:
European journal of biochemistry 2000 v.267 no.9 pp. 2609-2616
ISSN:
0014-2956
Subject:
Bacillus subtilis; acetonitrile; amyloid; cold shock proteins; models; nuclear magnetic resonance spectroscopy; polypeptides; solvents; wavelengths
Abstract:
... The peptide CspB‐1, which represents residues 1–22 of the cold shock protein CspB from Bacillus subtilis, has been shown to form amyloid fibrils when solutions containing this peptide in aqueous (50%) acetonitrile are diluted in water [M. Großet al. (1999) Protein Science8, 1350–1357] We established conditions in which reproducible kinetic steps associated with the formation of these fibrils can b ...
DOI:
10.1046/j.1432-1327.2000.01270.x

57. Comparison of migration modeling in micellar electrokinetic chromatography by linear regression and by use of an artificial neural network

Author:
H. J. Metting; P. V. van Zomeren; C. P. van der Ley; P. M. J. Coenegracht; G. J. de Jong
Source:
Chromatographia 2000 v.52 no.9-10 pp. 607-613
ISSN:
0009-5893
Subject:
acetonitrile; cocaine; linear models; methanol; micellar electrokinetic capillary chromatography; neural networks; neurons; prediction; regression analysis; sodium dodecyl sulfate; surfactants
Abstract:
... The concentrations of modifier (methanol or acetonitrile) and surfactant (sodium dodecyl sulfate, SDS) in the running buffer are important factors influencing the mobility of analytes in micellar electrokinetic chromatography (MEKC). Response surfaces of the effective mobility can be used to predict mobility as a function of the buffer composition.This paper describes the modeling, by multiple lin ...
DOI:
10.1007/BF02789760

58. Determination of sulfonylurea herbicides in soil extracts by solid-phase extraction and capillary zone electrophoresis

Author:
Z. L. Chen; R. S. Kookana; R. Naidu
Source:
Chromatographia 2000 v.52 no.3-4 pp. 142-146
ISSN:
0009-5893
Subject:
acetonitrile; capillary zone electrophoresis; chromatography; detection limit; pH; sodium acetate; sodium bicarbonate; soil; soil sampling; solid phase extraction; solutes; sulfonylurea herbicides
Abstract:
... Sulfonylurea herbicides in soil extracts were concentrated using off-line solid-phase extraction (SPE), and determined by capillary zone electrophoresis (CZE) and UV detection. The method involves extraction of soils with 0.1 M NaHCO₃ solution and subsequent preconcentration by using C₁₈ cartridges prior to separation of the pesticide using CZE. The results show that a C₁₈ cartridge is suitable fo ...
DOI:
10.1007/BF02490444

59. High performance liquid chromatography of aromatic and polyaromatic hydrocarbons on a new chemically bonded liquid crystal phase

Author:
O. Ferroukhi; N. Atik; S. Guermouche; M. H. Guermouche; P. Berdagué; P. Judenstein; J. P. Bayle
Source:
Chromatographia 2000 v.52 no.9-10 pp. 564-568
ISSN:
0009-5893
Subject:
acetonitrile; benzene; hexane; isomers; liquid crystals; polycyclic aromatic hydrocarbons; reversed-phase high performance liquid chromatography; separation; silicon; temperature; xylene
Abstract:
... The chromatographic behaviour of 15 aromatic and 20 polyaromatic hydrocarbons (PAHs) on a new HPLC bonded liquid crystal stationary phase called BLC is presented. BLC is 4-(4-carboxy-benzyloxy)-3-methyl-2-dodecyloxy-4′-(2-(4′-dodecyloxy-benzyl)-ethylene-azobenzene bonded to LiChrospher Si 100 NH2. The method for PAH separation involved n-hexane in normal-phase HPLC. In reversed phase HPLC, which w ...
DOI:
10.1007/BF02789751

60. Polymerization of guaiacol by lignin-degrading manganese peroxidase from Bjerkandera adusta in aqueous organic solvents

Author:
Iwahara, K.; Honda, Y.; Watanabe, T.; Kuwahara, M.
Source:
Applied microbiology and biotechnology 2000 v.54 no.1 pp. 104-111
ISSN:
0175-7598
Subject:
Bjerkandera adusta; acetone; acetonitrile; aromatic amines; calorimetry; crosslinking; desorption; dioxane; ethanol; ethylene glycol; gas chromatography-mass spectrometry; gel chromatography; guaiacol; ionization; manganese; manganese peroxidase; matrix-assisted laser desorption-ionization mass spectrometry; methanol; molecular weight; o-cresol; peroxidase; polymerization; polymers; pyrolysis; solvents
Abstract:
... Lignin-degrading manganese (II) peroxidase (MnP) purified from the culture of a wood-rotting basidiomycete, Bjerkandera adusta, was used in the polymerization of guaiacol. MnP was found to catalyze polymerization of guaiacol in 50% aqueous acetone, dimethyl formamide, methanol, ethanol, dioxane, acetonitrile, ethylene glycol and methylcellosolve. Maximum yield of polyguaiacol was achieved in 50% a ...
DOI:
10.1007/s002530000340
PubMed:
10952012

61. Prediction of the chromatographic behaviour for a series of diuretic compounds

Author:
J. Barbosa; R. Bergés; V. Sanz-Nebot
Source:
Chromatographia 2000 v.51 no.7-8 pp. 417-427
ISSN:
0009-5893
Subject:
acetonitrile; chromatography; dissociation; energy; pH; prediction; solvents
Abstract:
... The proportion of organic modifier and the pH of the acetonitrile-water mixtures used as mobile phases were optimized in order to separate a group of diuretic compounds covering a wide range of physyco-chemical properties. The Linear Solvation Energy Relationship (LSER) formalism based either on the multiparameter π*, β and α scales or the single solvent polarity parameterE T ᴺ , have been used to ...
DOI:
10.1007/BF02490478

62. Resolution of mixtures of steroidal hormones with micellar eluents of sodium dodecyl sulphate and acetonitrile or pentanol

Author:
S. Torres-Cartas; J. R. Torres-Lapasió; R. M. Villanueva-Camañas; M. C. García-Alvarez-Coque
Source:
Chromatographia 2000 v.52 no.3-4 pp. 185-189
ISSN:
0009-5893
Subject:
acetates; acetonitrile; chromatography; hydrophobicity; medroxyprogesterone; methyltestosterone; pentanols; prediction; progesterone; propionic acid; sodium dodecyl sulfate; testosterone
Abstract:
... An optimization strategy was applied to explore the capability of hybrid micellar eluents of sodium dodecyl sulphate (SDS), using acetonitrile or pentanol as modifiers, to resolve mixtures of eleven steroids showing a wide range of hydrophobicity (clostebol acetate, dehydrotestosterone, dydrogesterone, medroxyprogesterone, medroxyprogesterone acetate, methandienone, methyltestosterone, progesteron ...
DOI:
10.1007/BF02490454

63. Separation ofCimicifuga racemosa triterpene glycosides by reversed phase high performance liquid chromatography and evaporative light scattering detection

Author:
M. Ganzera; E. Bedir; I. A. Khan
Source:
Chromatographia 2000 v.52 no.5-6 pp. 301-304
ISSN:
0009-5893
Subject:
acetonitrile; alcohols; detection limit; glycosides; light scattering; markets; reversed-phase high performance liquid chromatography; triterpenoids; China
Abstract:
... The main triterpene glycosides ofCimicifuga racemosa were separated by reversed phase HPLC, using a C-18 column, Evaporative Light Scattering (ELS) detection and a grient system consisting of water, acetonitrile and reagent alcohol. Within 35 min three main glycosides could be separated and quantified in the methanolic root extract with detection limits of 10.5, 15.6 and 31.6 μg·mL⁻¹ respectively. ...
DOI:
10.1007/BF02491021

64. Simultaneous high-performace liquid chromatographic determination of sulfamonomethoxine and its hydroxy/N4-acetyl metabolites following centrifugal ultra-filtration in animal blood plasma

Author:
N. Furusawa
Source:
Chromatographia 2000 v.52 no.9-10 pp. 653-656
ISSN:
0009-5893
Subject:
acetic acid; acetonitrile; blood plasma; detection limit; food animals; high performance liquid chromatography; metabolites; sulfamonomethoxine; sulfanilamide
Abstract:
... A simple high-performance liquid chromatographic (HPLC) method was developed for the determination of sulfamonomethoxine (N¹-(6-methoxy-4-pyrimidinyl) sulfanilamide, SMM) and its hydroxy metabolites, i.e., N¹-(6-methoxy-2-hydroxy-4-pyrimidinyl) sulfanilamide (2-OH-SMM), N¹-(6-hydroxy-4-pyrimidinyl) sulfanilamide (6-OH-SMM), N¹-(2,6-dihydroxy-4-pyrimidinyl) sulfanilamide (2,6-diOH-SMM), and N⁴-acet ...
DOI:
10.1007/BF02789766

65. Simultaneous separation of nonionic surfactants and polyethylene glycols by reversed phase high performance liquid chromatography

Author:
T. Kamiusuki; T. Monde; K. Omae; K. Morioka; T. Konakahara
Source:
Chromatographia 2000 v.51 no.7-8 pp. 390-396
ISSN:
0009-5893
Subject:
acetonitrile; dodecanoic acid; ethylene oxide; light scattering; nonionic surfactants; polyethylene glycol; reversed-phase high performance liquid chromatography; silica gel; temperature
Abstract:
... The simultaneous separation of polyethylene glycol and its derivatives such as the lauryl alcohol and lauric acid ethoxylate oligomers was carried out by reversed phase high performance liquid chromatography. Branched fluorinated silica gel columns combined with evaporative light scattering detection were used for the characterization of nonionic surfactants. Lauryl alcohol ethoxylate oligomers we ...
DOI:
10.1007/BF02490474

66. An improved derivatization method for sensitive determination of fatty acids by high-performance liquid chromatography using 9-(2-hydroxylethyl)-carbazole as derivatization reagent with fluorescence detection

Author:
Jinmao You; Weibing Zhang; XiangIan Jia; Yukui Zhang
Source:
Chromatographia 2001 v.54 no.5-6 pp. 316-322
ISSN:
0009-5893
Subject:
acetonitrile; derivatization; detection limit; esters; fluorescence; high performance liquid chromatography; long chain fatty acids; molecular weight
Abstract:
... Tagging techniques with reagents used for fluorescent detection for short and long-chain fatty acids using high-performance liquid chromatography are evaluated in terms of the tagging reactions, handing, flexibility, stability of the reagents. Emphasis is given to the applications of the tagging techniques to relatively high molecular mass fatty acids. The fatty acids or carboxylic compounds were ...
DOI:
10.1007/BF02492676

67. Analysis of oxygen heterocyclic compounds in citrus essential oils by capillary electrochromatography and comparison with HPLC

Author:
A. Cavazza; K. D. Bartle; P. Dugo; L. Mondello
Source:
Chromatographia 2001 v.53 no.1-2 pp. 57-62
ISSN:
0009-5893
Subject:
Citrus; acetonitrile; electrochromatography; essential oils; heterocyclic oxygen compounds; high performance liquid chromatography; mandarins; oils; pH; silica; solvents; temperature
Abstract:
... A new method for the analysis of oxygen heterocyclic compounds in bergamot, mandarin and sweet organge oils by capillary electrochromatography (CEC) is reported. The fused silica capillaries employed were slurry-packed in house with 3 μm ODS1 stationary phase. The repeatability of the technique has been investigated with two neutral standard mixtures. Conditions for the analysis have been optimise ...
DOI:
10.1007/BF02492428

68. Determination of Fumonisins B1 and B2 Produced by Isolates of Gibberella fujikuroi Complex in Corn and Rice

Author:
J. J. Mateo; R. Mateo; M. Jiménez
Source:
Food science and technology international 2001 v.7 no.3 pp. 231-236
ISSN:
1082-0132
Subject:
Fusarium; acetonitrile; animal diseases; beta-mercaptoethanol; cleaning; corn; detection limit; fluorescence; food contamination; fumonisins; fungi; methanol; reversed-phase high performance liquid chromatography; rice; signal-to-noise ratio; solid phase extraction
Abstract:
... Fumonisins B1 (FB 1) and B2 (FB2) are the major mycotoxins produced mainly by some strains of Gibberella fujikuroi complex, fungi that occur worldwide on cereals. Contamination of food and feed with these fungi has been associated with a number of diseases in animals and humans. In this work, some steps in the analysis of FB 1 and FB 2 by HPLC to reduce analysis time, costs and impurities in the e ...
DOI:
10.1106/QN30-QG8C-2GPA-27EU

69. Determination of Recombinant human epidermal growth factor (rhEGF) in a pharmaceutical formulation by high performance liquid chromatography with electrochemical detection

Author:
Kang-Woo Lee; Kyung-Hwa Hwang; Chang-Soo Kim; Kun Han; Youn-Bok Chung; Jeong-Sook Park; Yong-Moon Lee; Dong-Cheul Moon
Source:
Archives of pharmacal research 2001 v.24 no.4 pp. 355
ISSN:
0253-6269
Subject:
acetonitrile; arginine; buffers; carbon; correlation; drug formulations; drugs; electrochemistry; electrodes; epidermal growth factor; high performance liquid chromatography; humans; methionine; oxidation; pH; phosphates; silver chloride; tryptophan; tyrosine
Abstract:
... A novel HPLC method with electrochemical detection has been developed for the determination of recombinant human epidermal growth factor (rhEGF) in pharmaceutical products. rhEGF was separated from other components in formulation on a reversed-phase C18 column with 24% acetonitrile in 0.1 M phosphate buffer (pH 4.75). The optimum electrochemical oxidation of EGF was obtained at 0.85 V vs. Ag/AgCl ...
DOI:
10.1007/BF02975106

70. Determination of benzylpenicillin, oxacillin, cloxacillin, and dicloxacillin in cows' milk by ion-pair high-performance liquid chromatography after precolumn derivatization

Author:
M. Marchetti; I. Schwaiger; E. Schmid
Source:
Fresenius' journal of analytical chemistry 2001 v.371 no.1 pp. 64-67
ISSN:
0937-0633
Subject:
acetonitrile; antibiotic residues; benzylpenicillin; derivatization; dicloxacillin; ethyl acetate; high performance liquid chromatography; hydrogen; lipids; mercury; milk; pH; phosphates; solid phase extraction; sulfates; tetrabutylammonium compounds; thiosulfates
Abstract:
... A high-performance liquid-chromatographic method has been developed for the determination of five penicillin compounds (benzylpenicillin, phenoxymethylpenicillin, oxacillin, cloxacillin, and dicloxacillin) at trace levels in commercially available milk samples. This method comprises extraction of the lipids with ethyl acetate, clean-up and concentration on a C-18 solid-phase extraction column, and ...
DOI:
10.1007/s002160100858

71. Determination of mycophenolic acid and its glucuronide conjugate in human plasma by capillary electrophoresis

Author:
S. Ünsalan; G. Hempel; J. Boos; G. Blaschke
Source:
Chromatographia 2001 v.54 no.9-10 pp. 635-637
ISSN:
0009-5893
Subject:
acetonitrile; buffers; capillary electrophoresis; chromatography; humans; metabolites; pH; silica
Abstract:
... In clinical transplantation mycophenolate mofetil (MMF) has become an attractive immunosuppressive agent. To quantify mycophenolic acid (MPA) and its main metabolite mycophenolic acid glucuronide (MPAG) from small plasma volumes, a capillary electrophoresis method has been developed. Separation of MMF and its metabolites MPA and MPAG was carried out in a 37 cm×50μm-l.D., fused silica, capillary wi ...
DOI:
10.1007/BF02492191

72. Determination of olanzapine and desmethylolanzapine in the plasma of schizophrenic patients by means of an improved HPLC method with amperometric detection

Author:
M. A. Raggi; R. Mandrioli; C. Sabbioni; N. Ghedini; S. Fanali; V. Volterra
Source:
Chromatographia 2001 v.54 no.3-4 pp. 203-207
ISSN:
0009-5893
Subject:
acetonitrile; detection limit; electrochemistry; high performance liquid chromatography; humans; metabolites; methanol; monitoring; pH; patients; phosphates; solid phase extraction
Abstract:
... An improved HPLC method with electrochemical detection has been developed for the determination of olanzapine and its main metabolite, desmethylolanzapine, in human plasma. Chromatographic separation and analysis were performed on a C₈ reversed-phase column with a mixture of methanol, acetonitrile, and pH 3.7 phosphate buffer as mobile phase; 2-methylolanzapine was used as internal standard. Caref ...
DOI:
10.1007/BF02492246

73. Effect of time, temperature and solvent on the stability of T-2 toxin, HT-2 toxin, deoxynivalenol and nivalenol calibrants

Author:
Widestrand, J.; Pettersson, H.
Source:
Food additives & contaminants 2001 v.18 no.11 pp. 987-992
ISSN:
0265-203X
Subject:
T-2 toxin; HT-2 toxin; nivalenol; deoxynivalenol; temperature; solvents; food analysis; duration
Abstract:
... The influence of solvent, storage time and temperature on the stability of the trichothecene mycotoxins T-2 toxin (T-2), HT-2 toxin (HT-2), deoxynivalenol (DON) and nivalenol (NIV) was investigated. Toxins in acetonitrile, ethyl acetate or as thin film were stored in sealed glass ampoules at -18, 4, 25 and 40 degrees C for up to 24 months. Samples were analysed by HPLC with UV detection. The resul ...
DOI:
10.1080/02652030110050168
PubMed:
11665740

74. Enzymatic Synthesis of Two Ginsenoside Re-β-xylosides

Author:
Sung-Ryong KO; Yukio SUZUKI; Young-Hoi KIM; Kang-Ju CHOI
Source:
Bioscience, biotechnology, and biochemistry 2001 v.65 no.5 pp. 1223-1226
ISSN:
1347-6947
Subject:
Aspergillus oryzae; Trichoderma viride; acetone; acetonitrile; biotechnology; endo-1,4-beta-glucanase; ginsenosides; hydrolysis
Abstract:
... Two new β-xylosyl derivatives of ginsenoside Re, 20(S)-protopanaxatriol 6-O-α-L-rhamnopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→4)]-β-D-glucopyranosyl-20-O-β-D-glucopyranoside and 20(S)-protopanaxatriol 6-O-α-L-rhamnopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→6)]-β-D-glucopyranosyl-20-O-β-D-glucopyranoside, were respectively synthesized from p-nitrophenyl β-D-xylopyranoside and phenyl β-D-xylopyranoside as ...
DOI:
10.1271/bbb.65.1223

75. Gas chromatographic determination of coumaphos and tau-fluvalinate residues in royal jelly produced under commercial conditions

Author:
Panos G Balayannis
Source:
Journal of apicultural research 2001 v.40 no.2 pp. 71-78
ISSN:
2078-6913
Subject:
acetonitrile; apiculture; centrifugation; coumaphos; fluvalinate; gas chromatography-mass spectrometry; isopropyl alcohol; methylene chloride; plywood; research; royal jelly; separation
Abstract:
... A gas chromatographic analytical method was developed and used to determine coumaphos (Perizin) and tau-fluvalinate (Apistan) residues in royal jelly. The method involves sample dilution with a mixture of isopropyl alcohol/acetonitrile, centrifugation for phase separation, extraction with methylene chloride and analysis by gas chromatography-mass spectrometry. Recoveries ranged from 82–93% with co ...
DOI:
10.1080/00218839.2001.11101054

76. HPLC separations of zidovudine and selected pharmaceuticals using a hexadecylsilane amide column

Author:
W. V. Caufield; J. T. Stewart
Source:
Chromatographia 2001 v.54 no.9-10 pp. 561-568
ISSN:
0009-5893
Subject:
acetonitrile; buffers; ceftazidime; drugs; heat; high performance liquid chromatography; hydrogen peroxide; intravenous injection; pH; phosphates
Abstract:
... Stability indicating high performance liquid chromatography methods have been developed for the assay of zidovudine in combination with either ceftazidime (A), chlordiazepoxide (B), dobutamine (C), lorazepam (D) or ranitidine (E) in intravenous fluid mixtures.All separations were performed on an amide hexadecylsilane column (250×4.6 mm) with 25 mM phosphate buffer, pH 3.0-acetonitrile eluent. Isoc ...
DOI:
10.1007/BF02492179

77. Improved method for the rapid determination of terpenoid aldehydes in cotton

Author:
Benson, C.G.; Wyllie, S.G.; Leach, D.N.; Mares, C.L.; Fitt, G.P.
Source:
Journal of agricultural and food chemistry 2001 v.49 no.5 pp. 2181-2184
ISSN:
0021-8561
Subject:
Gossypium hirsutum; Gossypium barbadense; leaves; bolls; seeds; terpenoids; aldehydes; gossypol; extraction; ultrasonic treatment; nitriles; water; centrifugation; automation; high performance liquid chromatography
Abstract:
... A simple, rapid method for the extraction of cotton terpenoid aldehydes from green tissues and seed is described. Samples were treated by ultrasonification with acidified acetonitrile/water followed by centrifugation. The resulting extract was injected directly onto a C18 HPLC column and no sample concentration or further cleanup steps were required. The level of gossypol, the most labile of the t ...
DOI:
10.1021/jf0010836
PubMed:
11368574

78. Influence of the solvent on the gas chromatographic behaviour of urea herbicides

Author:
H. Berrada; G. Font; J. C. Moltó
Source:
Chromatographia 2001 v.54 no.3-4 pp. 253-262
ISSN:
0009-5893
Subject:
acetonitrile; chlorotoluron; chlorsulfuron; detection limit; diuron; esters; ethanol; fluometuron; gas chromatography; ions; isoproturon; linuron; mass spectrometry; methanol; methylene chloride; metobromuron; monuron; solvents; temperature; triazines
Abstract:
... Degradation products of chlorsulfuron, chlortoluron, diuron, fluometuron, isoproturon, linuron, metabenzthiazuron, metobromuron, and monuron formed in the gas chromatographic injector have been used for identification of the respective herbicides. Mass spectra of the derived compounds were obtained with a quadrupole mass spectrometric detector working in scan mode (20–450 amu). The compounds gener ...
DOI:
10.1007/BF02492254

79. Multidimensional on-line solid-phase extraction (SPE) using restricted access materials (RAM) in combination with molecular imprinted polymers (MIP)

Author:
Karl-Siegfried Boos; Claudia Fleischer
Source:
Fresenius' journal of analytical chemistry 2001 v.371 no.1 pp. 16-20
ISSN:
0937-0633
Subject:
acetonitrile; analgesics; desorption; fractionation; high performance liquid chromatography; humans; milk; molecular imprinting; molecular weight; polymers; saliva; solid phase extraction; solvents; urine
Abstract:
... A novel, multidimensional SPE sample-processing platform for complex fluids, which relies on the combination of small LC columns packed with restricted access materials (RAM) and molecular imprinted polymers (MIP) is described. It is called the Six-S ProcEdure (Six-SPE). Six-SPE involves a size-selective sample-separation step followed by a solvent-switch. Six-SPE efficiently removes interfering m ...
DOI:
10.1007/s002160100831

80. Nachweis von Zearalenon-4-β-D-Glucopyranosid in Weizen

Author:
I Schneweis; K Meyer; G Engelhardt; J Bauer
Source:
Mycotoxin research 2001 v.17 no.Supplement 1 pp. 87-91
ISSN:
0178-7888
Subject:
Zea mays; acetonitrile; cell culture; corn; ethyl acetate; methanol; wheat; zearalenone
Abstract:
... Maize (Zea mays) cell cultures were used for the production of zearalenone-4-β-D-glucopyranoside as standard compound. Wheat samples were extracted with acetonitrile: water, applied to a florisil column and eluted with methanol:ethyl acetate. For determination and quantification of zearalenone-4-β-D-glucopyranoside and zearalenone a LC-MS method was developed. A concentration of 10 μg/kg zearaleno ...
DOI:
10.1007/BF03036719

81. Simple and rapid HPLC method for simultaneous determination of multiple antiepileptic drugs in human serum

Author:
G. A. Khoschsorur; F. Frühwirth; G. Halwachs-Baumann
Source:
Chromatographia 2001 v.54 no.5-6 pp. 345-349
ISSN:
0009-5893
Subject:
acetonitrile; analgesics; blood serum; humans; patients; phenobarbital; phenytoin; phosphoric acid; reversed-phase high performance liquid chromatography; temperature
Abstract:
... A very rapid, sensitive and reproducible HPLC method was developed for simultaneous determination of eight anti-epileptic drugs (AEDs): lamotrigine, primidone, ethosuximide, sulthiame, felbamate, phenobarbital, carbamazepine, phenytoin and oxcarbazepine-metabolite (10-hydroxy-carbazepine) in human serum. Sample purification requires only protein precipitation with an appropriate reagent. Separatio ...
DOI:
10.1007/BF02492681

82. ZONMAIZE: EU-SMT-Project for the production of Certified Reference Materials (CRM) for the determination of zearalenone in maize

Author:
R Krska; R Josephs; H Pettersson; S Mc Donald
Source:
Mycotoxin research 2001 v.17 no.Supplement 1 pp. 92-96
ISSN:
0178-7888
Subject:
acetonitrile; certification; corn; drying; exercise; homogenization; packaging; zearalenone; Europe
Abstract:
... This paper decribes the course of the project “ZONMAIZE” which has been funded by the European Commission within the Standards, Measurement and Testing Programme (SM&T). The project deals with the preparation and certification of both a maize naturally contaminated with zearalenone (ZON) (c=40–120 μg/kg, ZON in maize) and a blank maize material (<5 μg/kg ZON in maize) to improve the quality and co ...
DOI:
10.1007/BF03036720

83. A green chemical method for the direct conversion of alcohol tetrahydropyranyl ethers into the corresponding acetates

Author:
Takeshi Oriyama; Kumiko Kobayashi; Takeshi Suzuki; Mihoko Oda
Source:
Green chemistry 2002 v.4 no.1 pp. 30-31
ISSN:
1463-9270
Subject:
acetates; acetonitrile; alcohols; ethers; green chemistry; organobromine compounds; organochlorine compounds; sodium
Abstract:
... Alcohol tetrahydropyranyl ethers are readily converted into the corresponding acetates by the reaction with acetyl bromide in acetonitrile. Using various substituted acetyl chlorides with an equimolar amount of sodium iodide, tetrahydropyranyl ethers can be also transformed into the corresponding substituted acetates in high yields. This clean synthesis is a significant method for atom economy. ...
DOI:
10.1039/b108186c

84. A laser-induced fluorescence dual-fiber optic array detector applied to the rapid HPLC separation of polycyclic aromatic hydrocarbons

Author:
Sean J. Hart; Gregory J. Hall; Jonathan E. Kenny
Source:
Analytical and bioanalytical chemistry 2002 v.372 no.1 pp. 205-215
ISSN:
1618-2642
Subject:
absorbance; acetonitrile; factor analysis; fiber optics; fluorescence; high performance liquid chromatography; polycyclic aromatic hydrocarbons; prediction; rapid methods; soil; wavelengths
Abstract:
... A multi-channel detection system utilizing fiber optics has been developed for the laser-induced fluorescence (LIF) analysis of chromatographic eluents. It has been applied to the detection of polycyclic aromatic hydrocarbons (PAH) in a chromatographically overlapped standard mixture and to a complex soil sample extract obtained during fieldwork. The instrument utilizes dual-fiber optic arrays, on ...
DOI:
10.1007/s00216-001-1125-6

85. A polyoxometallate-templated coordination polymer: synthesis and crystal structure of [Cu₃(4,4′-bipy)₅(MeCN)₂]PW₁₂O₄₀·2C₆H₅CN

Author:
Chad Inman; Jacqueline M. Knaust; Steven W. Keller
Source:
Chemical communications 2002 v. no.2 pp. 156-157
ISSN:
1364-548X
Subject:
acetonitrile; chemical reactions; coordination polymers; copper; crystal structure
Abstract:
... The spherical phosphotungstate ion, PW₁₂O₄₀³⁻, has been used as a non-coordinating anionic template for the construction of a novel, three-dimensional Cu(i) coordination polymer. ...
DOI:
10.1039/b107305b

86. Air monitoring of aldehydes by use of hydrazine reagents with a triazine backbone

Author:
C. Kempter; T. Berkhoudt; Greve C. Tolbøl; K. Egmose; U. Karst
Source:
Analytical and bioanalytical chemistry 2002 v.372 no.5-6 pp. 639-643
ISSN:
1618-2642
Subject:
acetonitrile; air; aldehydes; detection limit; fluorescence; fluorescence emission spectroscopy; hydrazine; monitoring; nitrogen dioxide; ozone; reversed-phase liquid chromatography; silica gel; triazines
Abstract:
... Two hydrazine reagents, 4-N,N-dimethylamino-6-(4′-methoxy-1′-naphthyl)-1,3,5-triazine-2-hydrazine (DMNTH) and N-methyl-4-N′,N′-dimethylamino-6-(4′-methoxy-1′-naphthyl)-1,3,5-triazine-2-hydrazine (MDMNTH) have been synthesized and used for the determination of aldehydes in air samples. Test tubes with the reagents coated on silica gel were prepared and used for monitoring of carbonyls in air. After ...
DOI:
10.1007/s00216-002-1247-5

87. An unprecedented 1D ladder coordination polymer based on a pentanuclear copper(ii) 2,4,6-tris(dipyridin-2-ylamino)-1,3,5-triazine building block

Author:
Patrick Gamez; Paul de Hoog; Olivier Roubeau; Martin Lutz; Willem L. Driessen; Anthony L. Spek; Jan Reedijk
Source:
Chemical communications 2002 v. no.14 pp. 1488-1489
ISSN:
1364-548X
Subject:
acetonitrile; anions; chemical reactions; coordination polymers; copper; cupric nitrate; ligands
Abstract:
... Copper(ii) nitrate reacts with the rigid polydentate triple-connecting dpyatriz ligand in acetonitrile to an unprecedented infinite molecular ladder in which five-coordinated copper pseudo-dimers are bridged by nitrate anions and the coordination polymer chains are linked by hexacoordinated copper ions leading to the formation of large guest cavities. ...
DOI:
10.1039/b203394a

88. Application of LC-SIM-MS. Determination of a neurokinin receptor antagonist in human plasma by column-switching HPLC and automated sample processing

Author:
P. Heizmann; R. Hérissé; R. Gössl
Source:
Chromatographia 2002 v.55 no.Supplement 1 pp. S121
ISSN:
0009-5893
Subject:
acetonitrile; antagonists; clinical trials; databases; high performance liquid chromatography; humans; monitoring
Abstract:
... A sensitive and selective HPLC column-switching procedure with single-quadrupole massspectrometric detection has been developed for the determination of a neurokinin receptor antagonist in human plasma. The analyte and its deuterated internal standard were isolated from plasma by precipitation of protein with acetonitrile and the deproteinated sample was injected on to the trapping column of a col ...
DOI:
10.1007/BF02493367

89. Architectural formation of a conjugated bimetallic Pd(ii) complex via oxidative complexation and a tetracyclic Pd(ii) complex via self-assembling complexation

Author:
Toshiyuki Moriuchi; Masayuki Kamikawa; Seiji Bandoh; Toshikazu Hirao
Source:
Chemical communications 2002 v. no.14 pp. 1476-1477
ISSN:
1364-548X
Subject:
acetonitrile; chemical reactions; ligands; palladium
Abstract:
... The conjugated homobimetallic palladium(ii) complex [(L¹)Pd(qd)Pd(L¹)] (qd = quinonediimine) was obtained in a one-pot reaction by the in-situ oxidative complexation of 1,4-phenylenediamine with the palladium(ii) complex [(L¹)Pd(MeCN)] (H₂L¹ = N,N′-bis(2-phenylethyl)-2,6-pyridinedicarboxamide) while in the absence of an additional ligand [(L¹)Pd(MeCN)] was converted to the amide-bridged macrocycli ...
DOI:
10.1039/b203726m

90. Aurophilic complexes as gold atom sources in organic media

Author:
Manuel Bardají; Pawel Uznanski; Catherine Amiens; Bruno Chaudret; Antonio Laguna
Source:
Chemical communications 2002 v. no.6 pp. 598-599
ISSN:
1364-548X
Subject:
acetonitrile; amines; chemical reactions; gold; hydrogen; nanogold; nuclear magnetic resonance spectroscopy; oxygen; phosphine; phosphorus; solvents; stable isotopes; toluene; transmission electron microscopy; ultraviolet-visible spectroscopy
Abstract:
... The decomposition, either thermal or under H₂, of [O(AuᴵPR₃)₃](CF₃SO₃) (R = Ph 1, R = Me 2) in organic solvents has been studied by ³¹P{¹H} NMR, UV–vis spectroscopy and TEM; during the reaction, the phosphine acts as an efficient oxygen trap and gold nanoparticles are produced which may be stabilized by PVP in acetonitrile (mean diameter 4.5 nm) or oleylamine in toluene (mean diameter 9 nm). ...
DOI:
10.1039/b111679g

91. Coupling dirhodium units through terpyridine bridges: synthesis and structure of a novel molecular rectangle

Author:
Jitendra K. Bera; Cristian Saul Campos-Fernández; Clérac Rodolphe; Kim R. Dunbar
Source:
Chemical communications 2002 v. no.21 pp. 2536-2537
ISSN:
1364-548X
Subject:
acetonitrile; cations; chemical reactions; ligands; methanol; pyrazines
Abstract:
... The cation [Rh₂(μ-O₂CMe)₂(MeCN)₆]²⁺ reacts with the bis-terpyridine ligand 2,3,5,6-tetra-2-pyridylpyrazine (tppz) to yield the reduced compound [Rh₄(μ-O₂CMe)₂(tppz)₂(MeOH)₄]⁴⁺ whose structure is that of molecular rectangle with edges defined by short Rh–Rh and long Rh–tppz–Rh units. ...
DOI:
10.1039/b208164b

92. Determination of biogenic amines as dansyl derivatives in intestinal digesta and feces by reversed phase HPLC

Author:
M. T. Saarinen
Source:
Chromatographia 2002 v.55 no.5-6 pp. 297-300
ISSN:
0009-5893
Subject:
acetonitrile; ammonium acetate; biogenic amines; digesta; feces; fluorescence; humans; pH; perchloric acid; proteins; reversed-phase high performance liquid chromatography
Abstract:
... A new method was developed for the determination of fifteen biogenic amines in the intestinal digesta and feces of animal or human origin. The method involves the addition of an internal standard (heptylamine), extraction of the amines, and precipitation of the proteins with perchloric acid. The amines are derivatised with dansyl chloride, separated on a C18 column using gradient elution with 0.2M ...
DOI:
10.1007/BF02491662

93. Determination of bisphenol A in canned pet foods

Author:
Kang, Jeong-Hun; Kondo, Fusao
Source:
Research in veterinary science 2002 v.73 no.2 pp. 177-182
ISSN:
0034-5288
Subject:
acetonitrile; bisphenol A; canned foods; cans; cats; coatings; dogs; hexane; high performance liquid chromatography; humans; leaching; pet foods; solid phase extraction
Abstract:
... Bisphenol A (BPA) contamination of canned foods for human use has been studied, but there are no reports concerning BPA contamination of canned pet foods. The purpose of this study was to identify the levels of BPA in canned pet foods. A total of 26 samples (15 samples of cat food and 11 samples of dog food) were prepared for analysis by high-performance liquid chromatography. BPA in the samples w ...
DOI:
10.1016/S0034-5288(02)00102-9

94. Determination of simazine and cymoxanil in soils by microwave-assisted solvent extraction and HPLC with reductive amperometrical detection

Author:
O. López de Sabando; Z. Gómez de Balugera; M. A. Goicolea; E. Rodríguez; M. C. Sampedro; R. J. Barrio
Source:
Chromatographia 2002 v.55 no.11-12 pp. 667-671
ISSN:
0009-5893
Subject:
acetonitrile; cymoxanil; electrodes; high performance liquid chromatography; mercury; microwave treatment; phosphates; silver chloride; simazine; soil; soil sampling; solvents; temperature
Abstract:
... A microwave-assisted extraction (MAE) method was optimized for the herbicide simazine and the fungicide cymoxanil in soil samples. The experimental variables that affect MAE, such as temperature, extraction time and solvent volume, were studied. It was concluded that these pesticides could be efficiently extracted from soil samples in a microwave oven with 10 mL of acetonitrile at 90°C for 5 min T ...
DOI:
10.1007/BF02491780

95. Development of high performance liquid chromatography tandem mass spectrometric methods for the determination of a novel ascomycin-based immunoregulant in human whole blood and plasma: A case of potential analyte loss during sample collection

Author:
I. Fu; E. J. Woolf; B. Karanam; S. Vincent; B. K. Matuszewski
Source:
Chromatographia 2002 v.55 no.Supplement 1 pp. S137
ISSN:
0009-5893
Subject:
acetonitrile; adsorption; ammonium acetate; blood plasma; high performance liquid chromatography; humans; linear models; macrolides; mass spectrometry; monitoring; quality control; regression analysis; solid phase extraction; spectrometers
Abstract:
... Methods for the determination of a novel, ascomycin-based macrolide immunosuppressant in human plasma and whole blood are described. Following protein precipitation, the analyte and an internal standard were extracted from each matrix using solid phase extraction on an end-capped cyano column. The analytes were chromatographed on a Zorbax SB-CN analytical column (5.0 μm, 150×4.6 mm) with a mobile ...
DOI:
10.1007/BF02493370

96. Electrocatalytic carboxylation of benzyl chlorides at silver cathodes in acetonitrile

Author:
Abdirisak A. Isse; Armando Gennaro
Source:
Chemical communications 2002 v. no.23 pp. 2798-2799
ISSN:
1364-548X
Subject:
acetonitrile; carbon electrodes; carboxylation; carboxylic acids; catalytic activity; cathodes; electrochemistry; mercury; organochlorine compounds; silver
Abstract:
... Silver exhibits powerful electrocatalytic activities towards the reductive carboxylation of benzyl chlorides (RCl): in CO₂-saturated CH₃CN, reduction of RCl occurs at potentials that are about 0.6 V more positive than those of the same process at Hg or carbon electrodes and gives carboxylic acids in good to excellent yields. ...
DOI:
10.1039/b206746c

97. Friedel–Crafts acylation reactions using metal triflates in ionic liquid

Author:
James Ross; Jianliang Xiao
Source:
Green chemistry 2002 v.4 no.2 pp. 129-133
ISSN:
1463-9270
Subject:
Lewis acids; acetonitrile; acetylation; catalysts; catalytic activity; copper; green chemistry; ionic liquids; organochlorine compounds; regioselectivity; sulfonates
Abstract:
... Aromatic electrophilic substitution reactions such as benzoylation and acetylation catalysed by metal triflates have been conducted in an ionic liquid, [bmim][BF₄] (bmim = 1-butyl-3-methylimidazolium). Cu(OTf)₂ (OTf = trifluoromethanesulfonate) was found to be the most efficient catalyst used, affording quantitative conversion of benzoyl chloride and anisole to methoxybenzophenone within 1 h and w ...
DOI:
10.1039/b109847k

98. Nickel-catalyzed regioselective carbocyclization of ortho-halophenyl ketones with propiolates: an efficient route to disubstituted indenols

Author:
Dinesh Kumar Rayabarapu; Chien-Hong Cheng
Source:
Chemical communications 2002 v. no.9 pp. 942-943
ISSN:
1364-548X
Subject:
acetonitrile; catalytic activity; chemical reactions; ketones; nickel; regioselectivity; zinc
Abstract:
... Carbocylization of o-halophenyl ketones with propiolates in the presence of Ni(dppe)Br₂ and Zn powder in acetonitrile at 80 °C afforded the corresponding 2,3-disubstituted indenols. ...
DOI:
10.1039/b201473d

99. Novel photo-induced coupling reaction of 9-fluorenylidenemalononitrile with 10-methyl-9,10-dihydroacridine

Author:
Hong Jiang; You-Cheng Liu; Jing Li; Guan-Wu Wang; Yun-Dong Wu; Quan-Ming Wang; Thomas C. W. Mak
Source:
Chemical communications 2002 v. no.8 pp. 882-883
ISSN:
1364-548X
Subject:
X-ray diffraction; acetonitrile; chemical reactions; fluorenes; irradiation; nuclear magnetic resonance spectroscopy; ultraviolet radiation
Abstract:
... 9-Fluorenylidenemalononitrile reacts with 10-methyl-9,10-dihydroacridine in deaerated acetonitrile under irradiation with λ > 320 nm to give a coupling product 9-dicyanomethyl-9-(10′-methyl-9′-acridinyl)fluorene, characterized by X-ray crystallographic, MS and NMR analyses. ...
DOI:
10.1039/b201239a

100. Optimisation and validation of a generic method for the LC assay of six corticosteroids and salicylic acid in dermopharmaceutical forms

Author:
R. D. Marini; A. Pantella; M. A. Bimazubute; P. Chiap; Ph. Hubert; J. Crommen
Source:
Chromatographia 2002 v.55 no.5-6 pp. 263-269
ISSN:
0009-5893
Subject:
acetonitrile; adrenal cortex hormones; liquid chromatography; methylparaben; pH; phosphates; preservatives; salicylic acid; sorbic acid
Abstract:
... A generic method was developed for the liquid chromatographic (LC) assay of six corticosteraids and salicylic acid in different dermatological formulations containing methylparaben and propylparaben or sorbic acid as preservatives. An adequate separation was obtained using octadecylsilica as stationary phase and a mixture of acetonitrile (MeCN) and 25 mM phosphate buffer of pH 3.5 as mobile phase. ...
DOI:
10.1007/BF02491657