Direct links between carbonaceous chondrites and their parent bodies in the solar system are rare. The Winchcombe meteorite is the most accurately recorded carbonaceous chondrite fall. Its pre-atmospheric orbit and cosmic-ray exposure age confirm that it arrived on Earth shortly after ejection from a primitive asteroid. Recovered only hours after falling, the composition of the Winchcombe meteorite is largely unmodified by the terrestrial environment. It contains abundant hydrated silicates formed during fluid-rock reactions, and carbon- and nitrogen-bearing organic matter including soluble protein amino acids. The near-pristine hydrogen isotopic composition of the Winchcombe meteorite is comparable to the terrestrial hydrosphere, providing further evidence that volatile-rich carbonaceous asteroids played an important role in the origin of Earth’s water.

In recent years the environmental and human health impacts of volatile organic compounds (VOCs) have become more apparent, resulting in increased analysis demand. The gold-standard chromatographic techniques continue to be employed for most laboratory analyses. However, they have made only modest gains in productivity over the years, and these gains are primarily due to automated sample preparation and injection. Alternatively, significant productivity gains for VOC analysis through faster sample analysis and reduced instrument maintenance could be achieved by adopting direct mass spectrometry techniques such as selected ion flow tube mass spectrometry (SIFT-MS). This article demonstrates that routine analysis techniques such as quality control checks, method validation, the method of standard additions, and internal standards are readily applied to SIFT-MS, simplifying adoption of the technique. In addition, workflows for analysis of chromatographically challenging species are simplified by using SIFT-MS. Sample throughputs are increased two- to 25-fold depending on the analytical procedure.

Analysis of volatile organic compounds (VOCs) in water is conventionally conducted using gas chromatography (GC)-based methods, for which sample preparation demands are relatively high and throughput is relatively low due to the time taken to achieve chromatographic separation. Direct mass spectrometry (DMS) techniques such as selected ion flow tube mass spectrometry (SIFT-MS) have potential to analyze water headspace (HS) at high sensitivity with minimal sample preparation, eliminating preconcentration/purging and/or water management steps. However, the dearth of guidance for validation of DMS methods is an impediment to their adoption in routine analysis. This study applies and adapts an internationally recognized pharmaceutical industry guidance document for method validation to a prototypical SIFT-MS headspace analysis method for 17 toxic VOCs in water. The approach to validation is, however, applicable to any routine analysis conducted using SIFT-MS, and very likely to any methods developed using other DMS techniques. For the method developed and validated here, linearities (as measured by the linear regression coefficient, R 2 ) were better than 0.990 for all compounds. Repeatability (measured using relative standard deviation, RSD) was less than 10% for all compounds. Similar method performance was observed for accuracy and recovery. The performance criteria achieved by this HS-SIFT-MS method suggest it has potential application in environmental and pharmaceutical routine analyses, perhaps as a rapid screening tool.

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The toxicity of many volatile organic compounds (VOCs) means that the safety of polymeric and other materials in contact with, or near, pharmaceutical and food products must be assured through sensitive, quantitative measurement. The multiple headspace extraction (MHE) technique was developed in the 1980s to provide quantitative analysis of VOCs in condensed-phase samples. Selected ion flow tube mass spectrometry (SIFT-MS) is a direct-injection mass spectrometry (DIMS) technique that often significantly reduces the analysis time for routine VOCs in headspace compared to gas chromatography (GC) methods. Using the prototypical polystyrene system, this study represents the first detailed application of MHE to SIFT-MS, describing protocols for method development (including optimization of equilibration temperature and time, plus calibration), data evaluation, and adoption of the technique into routine analysis. MHE-SIFT-MS gives an eight-fold throughput advantage over MHE-GC while being highly repeatable (relative standard deviation, RSD, less than 2%).