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Researchers from the University of Rome have developed a strategy for the identification of underivatized short peptides in urine using graphitized carbon black (GCB) solid-phase extraction (SPE) and liquid chromatography–mass spectrometry (LC–MS).

In an effort to better understand the current application potential of microscale liquid chromatography (micro-LC), I picked up a few recent review articles from the literature. What one immediately appreciates from glancing through the literature for such information, is that there are a lot of different configurations and alternative formats, which can be placed under the micro-LC umbrella.

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In on-site environmental applications, representative sampling and proper replication are essential. For these reasons, recent work in thin-film solidphase microextraction has focused on the development of unique holders and customized samplers that are tailored for distinct sampling environments. Here, we explore the latest developments.

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The sample solvent can have a big impact on peak shape in both reversed-phase and hydrophilic interaction liquid chromatography (HILIC) separations, especially when large volumes are injected. Diluting the sample with weak solvent can be an effective solution to mitigate this problem, but we have to be careful to not lose analytes of interest to precipitation or phase separation.

Most manufacturers ship gas chromatographs with a small collection of consumable parts and accessories, such as extra ferrules, inlet liners, or septa, and a few instrument-specific tools. In earlier times, some convenience items might have been included as well, like a bubble flow meter or a small set of tools, but now it’s rare to find such things in the shipping boxes. This edition of “GC Connections” lists a number of essential items that should be on hand in every gas chromatography (GC) laboratory, their function, and how to use them effectively.

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Gel permeation chromatography/size-exclusion chromatography (GPC/SEC) is the standard technique to determine the molar mass distribution of synthetic macromolecules. However, some kinds of polymers (for example, polyolefins) are often only soluble in special solvents and require high temperatures to be used during the analysis to keep the sample completely dissolved. Therefore, for the analysis of these polymers, dedicated high temperature GPC systems are used. This article will discuss the pros and cons of both high temperature GPC/SEC and ambient GPC/SEC.