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Solid-phase microextraction (SPME) in conjunction with gas chromatography–mass spectrometry (GC–MS) is a simple and effective way to sample analytes. Ordinarily the coated fiber is rid of compounds during desorption in the GC, allowing for the analysis of a new sample. Carryover of the analyte between samples, however, is a problem with many chemicals. Our data shows that heating the fiber in a high temperature injection port for only 2 min between runs prevents carryover. The short heating between samples improves the linearity of the peak area versus concentration relationship over four orders of magnitude of concentration, with a limit of detection below 10-7 M in every case. Although carryover is an acknowledged problem with SPME fibers, such short conditioning steps are rarely considered as a means to eliminate it; this study suggests that they should be evaluated as an option.

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Solid-phase microextraction (SPME) in conjunction with gas chromatography–mass spectrometry (GC–MS) is a simple and effective way to sample analytes. Ordinarily the coated fiber is rid of compounds during desorption in the GC, allowing for the analysis of a new sample. Carryover of the analyte between samples, however, is a problem with many chemicals. Our data shows that heating the fiber in a high temperature injection port for only 2 min between runs prevents carryover. The short heating between samples improves the linearity of the peak area versus concentration relationship over four orders of magnitude of concentration, with a limit of detection below 10-7 M in every case. Although carryover is an acknowledged problem with SPME fibers, such short conditioning steps are rarely considered as a means to eliminate it; this study suggests that they should be evaluated as an option.

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Solid-phase microextraction (SPME) in conjunction with gas chromatography–mass spectrometry (GC–MS) is a simple and effective way to sample analytes. Ordinarily the coated fiber is rid of compounds during desorption in the GC, allowing for the analysis of a new sample. Carryover of the analyte between samples, however, is a problem with many chemicals. Our data shows that heating the fiber in a high temperature injection port for only 2 min between runs prevents carryover. The short heating between samples improves the linearity of the peak area versus concentration relationship over four orders of magnitude of concentration, with a limit of detection below 10-7 M in every case. Although carryover is an acknowledged problem with SPME fibers, such short conditioning steps are rarely considered as a means to eliminate it; this study suggests that they should be evaluated as an option.

Latest:

Solid-phase microextraction (SPME) in conjunction with gas chromatography–mass spectrometry (GC–MS) is a simple and effective way to sample analytes. Ordinarily the coated fiber is rid of compounds during desorption in the GC, allowing for the analysis of a new sample. Carryover of the analyte between samples, however, is a problem with many chemicals. Our data shows that heating the fiber in a high temperature injection port for only 2 min between runs prevents carryover. The short heating between samples improves the linearity of the peak area versus concentration relationship over four orders of magnitude of concentration, with a limit of detection below 10-7 M in every case. Although carryover is an acknowledged problem with SPME fibers, such short conditioning steps are rarely considered as a means to eliminate it; this study suggests that they should be evaluated as an option.

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This instalment describes several commonly used microextraction sample preparation techniques and their applications to forensic toxicology analysis. Solid-phase microextraction (SPME), microextraction by packed sorbent (MEPS), and different types of liquid-based microextraction (LPME), including single‑drop microextraction (SDME), hollow-fibre supported LPME, three-phase LPME, and dispersive liquid–liquid microextraction (DLLME), are discussed. Examples of application of these techniques to determine illicit drugs and drugs of abuse from various biological specimens are provided as well.

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All agencies have issued varying guidances for the approval of recombinant biosimilars of biopharmaceuticals, and all submittals are considered on a case-by-case basis. This instalment of “Focus on Biopharmaceutical Analysis” looks at the best methodologies for demonstrating their analytical comparability.

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This article explores the analytical challenges associated with HCP monitoring and reviews recent advances in HCP characterization, with special emphasis on high performance liquid chromatography mass spectrometry (HPLC–MS)-based methods and HCP enrichment techniques.

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ALMSCO Application Note

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This application note details an optimized method for the extraction and cleanup of pesticide residues from coffee using a QuEChERS extraction procedure followed by a silica gel SPE cleanup.

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The rising numbers of liquid chromatography–mass spectrometry (LC–MS)-based metabolomics applications and untargeted metabolism studies have increased the need for reliable chromatographic separations for a large quantity of molecules with widespread polarities.

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Wastewater analysis has become an established approach for retrieving additional epidemiological information about the use of illicit drugs, alcohol, and tobacco at the population level. Here, we present an overview of the recent analytical frameworks and workflows for target and suspect analyses using low- and high-resolution mass spectrometry and discuss the latest advances in wastewater-based epidemiology (WBE).

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This article looks at the practical benefits of microflow liquid chromatography–mass spectrometry (LC–MS) in bioanalysis applications.

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Nanomaterials offer exciting possibilities for improving separations with techniques such as TLC, SPME, and CE.

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Whole column imaging detection capillary isoelectric focusing (iCIEF) has been recognized as a powerful tool for biopharmaceutical development and quality control. Unlike conventional single point detection capillary electrophoresis (CE) systems, in which light absorbance or emission at a specific point along the separation capillary is monitored, iCIEF detects a line of light that is passed through and radiates from the entire separation capillary. As a result, sequential snapshots of the whole separation capillary at different times are obtained. This allows sample separation and interaction in real time to be observed during electrophoresis, enabling fast analytical method development, high resolution separation, and high sample throughput.

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In recent years, Huanglongbing (HLB), or citrus greening disease, has devastated citrus crops throughout the world. Penicillin G has been used to treat HLB infected trees with promising results. However, the metabolites produced from the degradation of penicillin G are known to cause potentially life-threatening allergic reactions; therefore, the concentration and presence of the metabolites must be carefully monitored. We have built and revised an analytical method based on Ultra High Performance Liquid Chromatography in combination with Tandem Mass Spectrometry (UHPLC-MS/MS) in order to identify and quantitate penicillin G and its major metabolites, penillic acid and penilloic acid, in citrus fruit and juice. Here, we discuss the chromatographic conditions and revisions that improved the precision and accuracy of our measurements.

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In recent years, Huanglongbing (HLB), or citrus greening disease, has devastated citrus crops throughout the world. Penicillin G has been used to treat HLB infected trees with promising results. However, the metabolites produced from the degradation of penicillin G are known to cause potentially life-threatening allergic reactions; therefore, the concentration and presence of the metabolites must be carefully monitored. We have built and revised an analytical method based on Ultra High Performance Liquid Chromatography in combination with Tandem Mass Spectrometry (UHPLC-MS/MS) in order to identify and quantitate penicillin G and its major metabolites, penillic acid and penilloic acid, in citrus fruit and juice. Here, we discuss the chromatographic conditions and revisions that improved the precision and accuracy of our measurements.

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Australia’s Great Barrier Reef (GBR) stretches over 2300 km and is composed of over 3000 individual reef systems. The health of the reef therefore often comes under international scrutiny. Hilton Swan from Southern Cross University in Australia has been investigating volatile organic compound (VOC) emissions from the Great Barrier Reef using gas chromatography–mass spectrometry (GC–MS). He recently spoke to us about this work.

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The detection limit, analytical precision, dynamic range, and robustness of a method for the targeted quantification of peptides using a capillary-flow LC–MS system were evaluated by spiking known amounts of isotopically labeled yeast peptides into a 500-ng yeast digest matrix.

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Describes the preparation of a reversed-phase monolithic column with an optimized porous structure to separate intact proteins using LC–MS.

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Interest in chromatography using hydrophilic interaction liquid chromatography (HILIC) has continued to build in recent years. Adoption of the technique has been slowed by experiences of poor reproducibility. In particular, reequilibration times in HILIC have been reported as being exceptionally long as compared to reversed-phase chromatography. In this study, reequilibration times in HILIC for both aqueous–organic gradients and buffer gradients are systematically explored. The results not only promise to improve method development practices, but also provide insight into HILIC retention mechanisms across mechanistically differing polar stationary phases.

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In March 2015, the International Agency for Research on Cancer (IARC) published a report that stated that glyphosate was “probably carcinogenic to humans”. Ever since, the use of this chemical has been highly controversial. In some countries, including the USA and Australia, there are already limit values in effect for the weed killer.

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In March 2015, the International Agency for Research on Cancer (IARC) published a report that stated that glyphosate was “probably carcinogenic to humans”. Ever since, the use of this chemical has been highly controversial. In some countries, including the USA and Australia, there are already limit values in effect for the weed killer.

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This article describes a workflow for the analysis of phenolic components in wine enabling confident differential analysis using high performance liquid chromatography (HPLC) in combination with low-field drift-tube ion mobility quadrupole time-of-flight mass spectrometry (IMS-QTOF-MS).

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A sensitive and selective liquid chromatography spectrometry mass spectrometry (LC–MS–MS) method to determine clenbuterol-like beta agonist residues in human hair was developed and validated.

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Polyolefin (PO) is the largest volume industrial polymer in the world for making a wide range of commercial products that touch nearly every aspect of our daily lives, such as automobile parts, pipes, packaging films, household bottles, baby diapers, and so on.

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Lawrence W. Potts, Emeritus Prof. of Chemistry, Gustavus Adolphus College reviews Mark F. Vitha's new book from Wiley, "Chromatography: Principles and Instrumentation."

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A look at the role of system suitability tests (SSTs) during performance qualification (PQ).