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The determination of the carcinogenic food processing contaminant furan by headspace sampling of foods is challenging because it can easily escape from the sample during preparation. Furan can also be easily formed as a by-product when the sample is heated in the headspace apparatus. This article describes a number of approaches to overcome these difficulties and alternative methods to quantify furan in a variety of matrices.

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Potentiometry is a new detection method for liquid chromatography (LC) and capillary electrophoresis (CE). The principle behind this method is familiar to chromatographers because the signals depend on the partitioning tendency of analytes over the sensor coating and the eluent. This partitioning provokes a change in the surface potential and the detection of these changes can be classified as "potentiometric". A conversion algorithm is needed to convert the generated signals to concentration-related tracings (chromatograms).

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A Deans switch, employing Agilent's Capillary Flow Technology, was configured on an Agilent 7890A GC equipped with dual ECD detectors. A method was developed for the analysis of fish oil for PCB contamination. The Deans switch was used to heart cut 7 indicator PCBs (IUPAC Numbers 28, 52, 101, 118, 138, 153 and 180) from the primary DB-XLB column on to a DB-200 column for further separation. Fish oil from a supplement capsule was simply diluted 1:10 in isooctane and injected directly. To prevent carryover, contamination and retention time shifts, the Deans switch was used to backflush the primary column at the end of each run.

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The performance of lubricating oil is significantly degraded by the presence of fuel contaminants such as gasoline and diesel. Recycled oil is particularly susceptible to this form of contamination. Consequently, producers and distributors of lubricating oil must go to great lengths to ensure the levels of fuel contamination are kept to a safe limit (typically 4–5%) in these products.

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A new high-throughput LC–MS/MS method meets the challenge of eliminating matrix effects for monitoring, with high specificity, polar organic pesticides such as glyphosate in food and water, while meeting targeted limits of detection.

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The concept of the limit of detection (LOD) has been, and still is, one of the most controversial in analytical chemistry. The multiple definitions and calculation methods proposed have contributed to this situation. Although in the last years, several international organizations, such as ISO or IUPAC, have tried to reach a consensus in their definitions and have issued guidelines for the estimation of this important parameter in chemical analysis, the subject is still a matter of scientific debate. In this article, we try to clarify the definition and provide guidelines to estimate LOD in chromatographic methods of analysis.

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The evaluation of the state of a biological sample before starting the complex analyses is a crucial step in proteomics studies. This paper compares planar polyacrylamide gel electrophoresis (SDS-PAGE) and capillary on-the-chip SDS GE (CGE-on-the-chip) in terms of the speed of analysis, sensitivity and flexibility. Snake venoms, which are heterogeneous with high bioactivity and consist mainly of proteins with a molecular weight mass range below 100 kDa, were investigated. CGE-on-the-chip was found to be a faster and more stable technique, providing more information than classical SDS-PAGE. CGE-on-the-chip was also capable of detecting many compounds over a broad molecular weight mass range whereas the SDS-PAGE is more time-consuming and provides acceptable resolution either in the very low (below 17 kDa) or in the mid- to high-molecular mass region (16–200 kDa) depending on the gel/buffer-system selected.

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Potentiometry is a new detection method for liquid chromatography (LC) and capillary electrophoresis (CE). The principle behind this method is familiar to chromatographers because the signals depend on the partitioning tendency of analytes over the sensor coating and the eluent. This partitioning provokes a change in the surface potential and the detection of these changes can be classified as "potentiometric". A conversion algorithm is needed to convert the generated signals to concentration-related tracings (chromatograms).

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Accurate mass measurements are a key element of chemical characterization. However, the accepted mass accuracy tolerance of 3–5 ppm can still leave significant ambiguity in the proposed chemical formula. Consequently a further input from other analytical techniques such as NMR or MS/MS, along with some judgment based on the synthetic history is often required to arrive at a confident formula assignment.

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An effective metabolite identification study should ideally include both qualitative and quantitative information that for both identifying metabolites, and determining the rate of clearance and the metabolic routes of the parent drug. Liquid chromatography–mass spectrometry (LC–MS) is considered the standard analytical technique for metabolite identification studies. To date, however, qualitative and quantitative information has always been obtained from two separation platforms: quadrupole time-of-flight (QTof) MS for the exact mass full-scan qualitative study, and tandem quadrupole MS for the multiple reaction monitoring (MRM) quantitative study. With advancements to QTof instrumentation, specifically, recent improvements in sensitivity and dynamic range, it is now possible to perform both qualitative and quantitative experiments on a single QTof mass spectrometer. This article describes a workflow that allows simultaneous qualitative and quantitative metabolite identification studies to be..

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The acid-base constants of the most frequently used antianginals (diltiazem, nadolol, propranolol and verapamil) were determined using capillary zone electrophoresis (CZE). This method is based on measuring the electrophoretic mobility of the solute as a function of pH. The buffer employed was composed of borate-phosphate buffered across the pH range of 3.0–11.2. The acid-base constants were determined by performing linear and non-linear regression on the data obtained. The results were compared with those reported in literature and with those obtained by a spectrophotometric method. After comparison of the values, no significant differences were observed between the three acid-base constants.

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The increased resolving power provided by comprehensive two-dimensional gas chromatography (GCxGC) extends the chromatographer's ability to rapidly detect and measure smaller components in complex mixtures beyond that which was possible previously, allowing for the identification of hazardous components in complex mixtures such as foodstuffs or emergency response samples. In target analysis, the increased numbers of peaks resulting from the sample matrix can be largely ignored during the review of data. However, when the nature of the analyte of interest is not entirely known, analysis of the samples might require screening through the entire peak table for compounds with specific chemical characteristics. For example, in the analysis of foodstuffs for pesticides (1,2), GCxGC coupled with a time-of-flight mass spectrometry (GCxGC–TOF-MS) can provide low detection limits for multiple analytes in these complex samples. Yet the question remains as to whether other toxic compounds, not included in the..

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This article describes and compares a number of approaches to increase the speed of liquid chromatographic separations. On a standard LC column, a gain of a factor two in the run time (from 10 to 5 minutes) was achieved by increasing the flow-rate two-fold. On a monolithic column, a column operated at high temperature (120 ?C) and a short column, flow-rates could be increased typically five-fold, resulting in run times in the order of 2 minutes. This was accompanied by a sometimes considerable loss in separation efficiency. A combination of a very short run time and unaffected separation efficiency was realized on a UPLC system, designed for use at higher pressure. By working at approximately 800 bar, the analytes could be well separated within 30 seconds.

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A novel automated ultratrace gas chromatography–mass spectrometry (GC–MS) method has been developed that quantitates the eight toxaphene Parlar congeners designated in U.S. Environmental Protection Agency Method 8276. This method, combined with an efficient extraction, cleanup, and fractionation technique, makes is possible to extend instrument detection limits to the low parts-per-trillion concentration level for these toxaphene Parlar congeners.

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This article presents the findings from an analysis conducted on sensitivity in GC on the basis of the complex group of polycyclic aromatic hydrocarbons and PAH derivatives.

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The authors review chromatographic separations of archaeological biomolecules for their analysis using accelerator mass spectrometry or isotope ratio mass spectrometry.

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State-of-the-art mass spectrometry (MS) techniques of growing importance to life sciences research now include not just liquid chromatography (LC)–MSn (n = 2–11), but also LC–matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF), LC-MALDI-TOF-TOF, electrospray ionization (ESI)-TOF, and LC-Fourier transform (FT) MS.

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Potentiometry is a new detection method for liquid chromatography (LC) and capillary electrophoresis (CE). The principle behind this method is familiar to chromatographers because the signals depend on the partitioning tendency of analytes over the sensor coating and the eluent. This partitioning provokes a change in the surface potential and the detection of these changes can be classified as "potentiometric". A conversion algorithm is needed to convert the generated signals to concentration-related tracings (chromatograms).

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This article presents the findings from an analysis conducted on sensitivity in GC on the basis of the complex group of polycyclic aromatic hydrocarbons and PAH derivatives.

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The current final FDA guidance document discussing the revised scope and applicability of 21 CFR Part 11 clearly adopts a risk-based approach to Part 11 compliance. This is certainly a very pragmatic approach and one that many regulated firms had adopted even before the recent release of this document. This article will discuss the particulars of a risk-based approach to Part 11 compliance. The favored risk assessment protocols such as HACCP, FMEA and FMECA will also be addressed as well as how one can apply them to 21 CFR Part 11 compliance.

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The performance of lubricating oil is significantly degraded by the presence of fuel contaminants such as gasoline and diesel. Recycled oil is particularly susceptible to this form of contamination. Consequently, producers and distributors of lubricating oil must go to great lengths to ensure the levels of fuel contamination are kept to a safe limit (typically 4–5%) in these products.

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Most recently formulated pesticides are smaller in molecular weight and designed to break down rapidly in the environment.

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High-performance liquid chromatography (HPLC) is a powerful tool for the enantioselective separation of chiral drugs. However, the selection of an appropriate chiral stationary phase (CSP) and suitable operating conditions is a bottleneck in method development and a time- and resource-consuming task. Multimodal screening of a small number of CSPs with broad enantiorecognition abilities has been recognized as the best strategy to achieve rapid and reliable separations of chiral compounds. This paper describes the generic screening strategy developed at Johnson & Johnson Pharmaceutical Research and Development (J&J PRD) to successfully develop enantioselective HPLC methods for chiral molecules of pharmaceutical interest.

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With the threat of terrorism growing, the development of analytical techniques for the detection and identification of chemical warfare agent defradation products has increased. Capillary electrophoresis (CE) presents interesting features for this application.

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The 59th Annual Pittsburgh Conference and Exposition on Analytical Chemistry and Applied Spectroscopy (Pittcon 2008) will be held at the Ernest N. Morial Convention Center, New Orleans, Louisiana, USA, from 2–6 March, 2008. Pittcon 2008's Technical Program will be in the format of invited symposia, organized contributed oral sessions, contributed oral sessions, workshops, new product forums and poster sessions to cover the latest developments in the traditional and emerging disciplines of analytical chemistry and applied spectroscopy. Following on from last year's success, the networking sessions will be expanded.

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This article gives an overview of the performance of a previously developed system for the ranking of C18 reversed-phase columns applied to different pharmaceutical analyses. The separation of eight different drug substances from their respective impurities was studied. The chromatographic procedure for acetylsalicylic acid, clindamycin hydrochloride, buflomedil hydrochloride, chloramphenicol sodium succinate, phenoxymethylpenicillin and nimesulide was performed according to the corresponding European Pharmacopoeia monograph. The separations of dihydrostreptomycin sulphate and vancomycin were performed according to literature. It was found that that the column ranking system is a helpful tool in the selection of suitable columns in these analyses.

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State-of-the-art mass spectrometry (MS) techniques of growing importance to life sciences research now include not just liquid chromatography (LC)–MSn (n = 2–11), but also LC–matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF), LC-MALDI-TOF-TOF, electrospray ionization (ESI)-TOF, and LC-Fourier transform (FT) MS.

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Cleaning validation is a major analytical application in the pharmaceutical industry. Here, high performance liquid chromatography (HPLC) with charged aerosol detection is compared and contrasted to HPLC with UV detection showing comparable performance and several advantages for charged aerosol detection, especially for analytes that do not contain a chromophore.