Showing papers in "Journal of Chromatography A in 2005"

TL;DR: The selection of HSCCC conditions step by step including the selection of two-phase solvent systems, determination of partition coefficient (K) of analytes, preparation of two -phase solvent system and sample solution, selection of elution mode, flow rate, rotation speed, and on-line monitoring of the eluate are explained.

TL;DR: A review of the liquid chromatography-tandem mass spectrometry (LC-MS/MS) based methods published so far for the determination of pharmaceuticals in the environment is presented.

TL;DR: A method to determine a wide range of poly- and perfluorinated acids in environmental and biological matrices can be achieved with the use of high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), with a method detection limit in the range of several tens to hundreds of parts-per-quadrillion (pg/L) in water and at a few tens to several parts- per-trillion levels in biologicalMatrices.

TL;DR: The most obvious conclusion is that, today (reversed-phase) liquid chromatography combined with tandem mass spectrometric detection--either triple-quadrupole or ion-trap multi-stage--is the preferred technique in a large majority of all cases.

TL;DR: The retention of the acids on the amino phase decreased with increasing salt concentration in the mobile phase due to the ion-exchange effect, and the retention process was endothermic as opposed to exothermic on other phases.

TL;DR: A multi-residue method is developed and optimized for the extraction of 21 phenols and acids in sewage influent and effluent and reports, for the first time, the occurrence of 2-phenylphenol and parabens in those sewage samples.

TL;DR: An analytical method with two extraction steps has been developed and validated for the simultaneous determination of 30 pharmaceuticals belonging to various therapeutic categories in urban wastewater to boost the little available information on drugs' fates in sewage treatment plants (STPs) and in the receiving surface water.

TL;DR: Recent analytical applications of the pressurized liquid extraction technique in the extraction of contaminant compounds and matrix components in food and biological samples are explored, placing special emphasis on the strategies followed to obtain a rapid, selective, efficient and reliable extraction process.

TL;DR: The theory of peak capacity for the standard operating conditions of reversed-phase and ion-exchange chromatography is outlined and bandspreading phenomena in gradient chromatography are analyzed.

TL;DR: Compared to the widely used commercially available SPME fibers, this proposed disposable IL-coated fiber has much lower cost per determination, comparable reproducibility (RSD < 11%), and no carryover between each determination.

TL;DR: Results indicate that watermelon rind, an underutilized agricultural waste, offers a source of natural citrulline, which is used in the nitric oxide system in humans and has potential antioxidant and vasodilatation roles.

TL;DR: A new and simple extraction technique, coupled with a reversed-phase high performance liquid chromatography (RP-HPLC), was developed for the simultaneous concentration and analysis of testosterone (T) and epitestosterone (ET) in human urine.

TL;DR: The accuracy of the method was confirmed by comparing analytical data to certified values from reference materials for deoxynivalenol and zearalenone and the method performance characteristics were estimated after analysis of spiked blank maize samples.

TL;DR: In this review, the action principles, features of chromatography media regarding physical and chemical properties will be described and an attempt will be made to establish categories of different media.

TL;DR: Two GC-based methods modified for extraction and quantification of PHB, PHV and PH2MV from enhanced biological phosphorus removal (EBPR) systems are presented.

TL;DR: Hydrophilic interaction liquid chromatography was examined for the separation of paralytic shellfish poisoning (PSP) toxins using the stationary phase TSK-gel Amide-80 using a high degree of selectivity and sensitivity.

TL;DR: Pressurized liquid extraction was optimized and validated for the determination of sulfonamide and macrolide antimicrobials and trimethoprim in sewage sludge samples and results obtained were significantly lower for sulfonamides and in tendency lower for macrolides.

TL;DR: Polyethylene glycols (PEG) and PEG methyl ethers were generated from non-ionic fluorinated surfactants beside their oxidation products--aldehydes and acids--all identified by tandem (MS-MS) or multiple stage mass spectrometry (MSn).

TL;DR: Analytical methods have been developed that allow for the determination of antiphlogistics, lipid regulators, the antiepileptic carbamazepine, cytostatic agents, the psychiatric drug diazepam and iodinated contrast media as well as two major polycyclic musk fragrances in activated and digested sludge.

TL;DR: The developed method was applied to the determination of 67 foodstuffs, comprising soft drinks, jams, sauces, canned fruits/vegetables, dried vegetables/fruits and others, and found the range of preservatives found were from not detected to not detected.

TL;DR: The present paper provides a summary of the collision-induced dissociation of protonated and deprotonated phase II metabolites of drugs and pesticides, and the fragmentation of the major classes of conjugates is reported.

TL;DR: A simultaneous method for the determination of six tetracyclines (TCs) and five sulfonamides (SAs) using solid-phase extraction followed by liquid chromatography-ion trap tandem mass spectrometry for WWTP water matrices fell within an acceptable range of 15% absolute.

TL;DR: The recoveries obtained, confirm the usefulness of the proposed methodology for the analyses of these kind of complex samples with a high fat content, and the obtained detection limits meet the requirements established by the olive oil pesticide regulatory programs.

TL;DR: An improved quantification procedure for the analysis of chlorinated paraffins (CPs) is presented based on electron capture negative ionization mass spectrometry that compensates differences in response factors between reference CP mixtures and the CP pattern present in environmental samples.

TL;DR: The PCP-imprinted amino-functionalized silica gel sorbent exhibited high selectivity and offered a fast kinetics for the adsorption and desorption of PCP and offered good linearity for on-line solid-phase extraction of trace levels ofPCP.

TL;DR: This review compiles, compares, and discusses the results and observations found in published methods, while focusing on chemical principles in order to increase the practicing chemist's understanding of TCs to aid him/her in developing useful analyses.

TL;DR: The use of labelled glyphosate as internal standard allowed improving the recovery and precision for glyphosate and AMPA, while it was not efficient for glufosinate, that was quantified by external standards calibration.

TL;DR: The major drawbacks and pitfalls of proteomics the authors have observed in the laboratory and in particular during the application of proteomic technologies in the investigation of the brain are discussed.

TL;DR: The essential results are that many parameters depend on the inlet pressure, hence on the flow rate, and while reproducibility of results obtained at constant pressure and flow rate will not be affected, method development becomes far more complex because of the pressure dependence of everything.

TL;DR: Morphology of monolithic materials was studied by scanning electron microscopy and mercury intrusion porosimetry and the ratio of phase volume and the degree of crosslinking influenced the void size and pore size distribution of resulting polymers.