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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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Comprehensive two-dimensional liquid chromatography (LC×LC) is a powerful technique for separating highly complex samples. However, the proliferation of this technique is hindered by a range of challenges, including the possible impact of the additional separation on the detection sensitivity, concerns that mobile phase incompatibility problems will limit the applicability, and the complexity of the system and associated method development costs. This article addresses these issues and describes how modern modulators and software tools are overcoming the barriers associated with this technique.

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The biomimetic gradient retention time measurements on C18, immobilized artificial membrane (IAM), human serum albumin (HSA), and acid-glycoprotein (AGP) stationary phases can be used to characterize compounds partitioning into phospholipids and proteins. The data obtained can then be used in equations to estimate the in vivo plasmaÐtissue distribution of the compounds measured. The plasma protein binding, brain tissue binding, and in vivo drug efficiency can also be calculated using the biomimetic chromatographic data.

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We explore the careers and achievements of the winners of LCGC’s 11th annual awards: Ronald E. Majors and Zachary S. Breitbach.

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This article introduces the development of an automated and versatile technique for solution viscosity determination of a wide range of polymeric materials in different solvents. Sample preparation is a tedious and error-prone process in viscosity determinations of polymeric materials, especially when elevated temperature or when hazardous solvents are required. This new approach automates sample preparation and injection to the viscometer detector, with benefits in efficiency and safety as well as in analysis precision. The dissolution conditions were studied and optimized to reduce thermal and oxidative degradation, which are detrimental to the accuracy of the observed viscosity.

I do not remember the application, but I remember very clearly Professor McNair telling us that soil is one of the most challenging sample matrices, if not the toughest, from which to perform analytical determinations. Sources indicate the composition of soil ideal for growing plants to be 25% air, 25% water, 45% minerals, and 5% organic matter. That does not seem like a daunting makeup, but the reality is that the relative proportion of the constituents can vary dramatically.