Showing papers in "Journal of Chromatography A in 1996"

TL;DR: The chiral analyses of drugs in real samples like biological fluids or pharmaceutical formulations are reported and several chiral selectors have been successfully used in CE for chiral separation, including cyclodextrins and their derivatives.

TL;DR: In this article, a tentative chiral recognition model is proposed for DNB-amino acids which are resolved into enantiomers with exceptionally high α-values (e.g., DNBLeu with an α-value of about 7).

TL;DR: Derivatization reactions for the determination of amines by GC are reviewed with respect to reactivity, selectivity and sensitivity.

TL;DR: The glycopeptide antibiotic teicoplanin is shown to be a highly effective stationary phase chiral selector for the resolution of underivatized amino-acid and imino-acid enantiomers and the enantioselective separation mechanism is examined using both molecular modeling and retention data.

TL;DR: The theoretical background of C EC is discussed, the feasibility of CEC as a high-efficiency reversed-phase separation technique is demonstrated, theoretically achievable results to those obtained in practice are compared and fundamental studies on operational parameters such as dependence of EOF and efficiency on pH and organic modifier content are presented.

TL;DR: For 23 structurally unrelated compounds, solute capacity factors measured on IAM columns correlate very well with the solute equilibrium partition coefficients measured in fluid liposome systems (r = 0.907), which indicates that solute partitioning between the IAM bonded phase and the aqueous mobile phase is similar to the solutesome-aqueous phase.

TL;DR: The relationship between the various expressions that can be used to calculate binding constants with CE is shown and the advantages, limitations and proper use of the various approaches are discussed.

TL;DR: Highperformance anion-exchange chromatography (HPAEC) is a powerful tool for carbohydrate analysis as discussed by the authors, which requires no pre- or post-column derivatization, and yet offers superb resolution and sensitiviy.

TL;DR: In this paper, the analysis of organic compounds from aqueous samples by solid-phase microextraction (SPME) coupled to gas chromatography (GC) is reviewed with special emphasis on the determination and monitoring in environmental samples contaminated by organic micropollutants, i.e., benzene, toluene, ethylbenzene and xylene isomers (BTEX), pesticides, phenols and polycyclic aromatic hydrocarbons (PAH).

TL;DR: A simple and fast high performance liquid chromatography analysis method for eight tea catechins and caffeine using an ODS column and a water-acetonitrile-phosphoric acid mobile phase system was developed as discussed by the authors.

TL;DR: The mesoporous aluminosilicate MCMMCM-41 as mentioned in this paper is an ordered mesopore material with a regular pore structure composed of an assembly of hexagonal tubes with a pore diameter of 4 nm.

TL;DR: A review concerning the determination of pesticide residues in fruit and vegetables is presented and consideration is given to solid phase and supercritical extraction techniques, automation and robotic systems, and immunoassay procedures.

TL;DR: A solid-phase microextraction (SPME) procedure has been developed to successfully extract eighteen chlorine-containing pesticides from water using a fused-silica fiber coated with a non-polar polydimethylsiloxane stationary phase.

TL;DR: The applicability of linear solvation energy relationships (LSERs) to reversed-phase liquid chromatography (RPLC) was studied by examining the retention of a wide variety of aliphatic and aromatic compounds over the range of 20-50% (v/v) acetonitrile, methanol and tetrahydrofuran as discussed by the authors.

TL;DR: In this paper, a high-performance liquid chromatographic method is described, using an octadecylsilylated silica column for simultaneous quantitative determination of the bioactive terpene acids: asiatic acid, madecassic acid and their respective glycosides.

TL;DR: In this paper, the chiral separations of the neutral enantiomers of chlorthalidone by packed capillary electrochromatography was successfully achieved using two approaches: (a) use of chiral agent, hydroxypropyl-β-cyclodextrin (HPβCD) directly in the mobile phase with an achiral stationary phase (3 μm ODS), and (b) using of a chiral stationaryphase (5 μm HPβCD-bonded silica particles) with an chiral mobile phase.

TL;DR: In this article, the use of size-exclusion chromatography for determination of pore dimensions of chromatography media is reviewed, and the influence of various parameters, e.g., solute shape, pore shape, method errors, etc., is discussed.

TL;DR: A survey of recent developments in the separation and analysis of carbohydrates by high-performance liquid chromatography, in adsorption or partition modes, on polar sorbents with less polar eluents is given in this paper.

TL;DR: In this article, an on-line coupling of liquid chromatography with ion spray mass spectrometry (LC-ISP-MS) was used to identify tannin polymers.

TL;DR: In this paper, a sensitive, specific and highly reproducible method for the analysis of the two antineoplastics, ifosfamide and cyclophosphamide, in sewage water at the ppt-level is presented.

TL;DR: In this paper, a simple method to coat a non-ionic hydrophilic polymer onto the inner wall of a bare fused-silica capillary is established, and four basic proteins were separated by this method around pH 3-7 with phosphate buffer.

TL;DR: In this paper, solid phase microextraction (SPME) using polyacrylate has been applied as an alternative simple method for the analysis of 20 organophosphorus insecticides from environmental water samples.

TL;DR: This review presents application vignettes of a technically simple, yet analytically powerful method called fluorophore-assisted carbohydrate electrophoresis (FACE), which can be used for performing routine oligosaccharide profiling, monosACcharide analysis, and sequencing of a variety of carbohydrates.

TL;DR: The different parameters which can influence amine recoveries are considered; experience with different foods such as cheese, fish and meat preserves are reported and for each of them the optimized analytical procedure is described.

TL;DR: A new method for the simultaneous determination of all of these compounds, except ellagic acid, in juices by reversed-phase high-performance liquid chromatography (HPLC) using ultraviolet detection and involving isocratic elution is presented.

TL;DR: In this paper, the resveratrol was quantified in samples of two unusual Italian wines, Recioto (sweet) and Amarone (dry), produced with the same cultivar mixture in the same area (Valpolicella, Verona, Italy).

TL;DR: Developments to be expected in the near future in sensitive detection modes for carbohydrates after separation by capillary electrophoretic methods are outlined, focusing on the needs in glycobiology such as improved sensitivity and selectivity.

TL;DR: The technique of matrix-assisted laser desorption/ionization mass spectrometry (MALDI) is described and examples are given of its use for the examination of glycoproteins, glycopeptides, glycolipids and oligosaccharides.

TL;DR: A new method of electrochromatography is described in which a 50-microns capillary is etched with ammonium hydrogen difluoride, followed by modification of the new surface via a silation reaction with triethoxysilane to produce a hydride intermediate, and subsequently subjected to hydrosilation using 1-octadecene.

TL;DR: Typical applications of MEKC analysis are surveyed, including separation of closely related peptides and isotopic compounds, separation of very complex mixtures, determination of drugs in the biological samples, etc.