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Rationale: Small amounts of biofluid samples are frequently found at crime scenes; however, existing gold standard methods such as LC–MS frequently require destructive extraction of the sample before a time‐consuming analysis which puts strain on forensic analysis providers and can preclude further sample analysis. This study presents the application of sheath‐flow probe electrospray ionization‐mass spectrometry (sfPESI–MS) to the direct analysis of drug metabolites in dried blood spots (DBS) as a high throughput, minimally destructive alternative. Methods: A rapid direct analysis method using a sfPESI ionisation source coupled to an Orbitrap Exactive mass spectrometer was applied to detect cocaine metabolites (benzoylecgonine, BZE, cocaethylene, CE, and ecgonine methyl ester, EME) from DBS. An optimisation study exploring the use of different chemical modifiers (formic acid and sodium acetate) in the sfPESI probe extraction solvent was conducted to enhance the sensitivity and reproducibility of the sfPESI–MS method. Results: Optimisation of the extraction solvent significantly enhanced the sensitivity and reproducibility of the sfPESI–MS method. A quantitative response over a five‐point calibration range 0.5 to 10 μg/ml was obtained for BZE (R2 = 0.9979) and CE (R2 = 0.9948). Limits of detection (LOD) of 1.31, 0.29 and 0.15 μg/ml were achieved for EME, BZE and CE, respectively, from 48 h aged DBSs with % RSD (relative standard deviation) across the calibration range ranging between 19%–28% for [BZE + H]+, 13%–21% for [CE + H]+ and 12%–29% for [EME + H]+. Conclusions: A rapid (< 20 s) quantitative method for the direct analysis of cocaine metabolites from DBS which requires no prior sample preparation was developed. Although the LOD achieved for BZE (LOD: 0.29 μg/ml) was above the UK threshold limit of exposure for drug driving (0.05 μg/ml), the method may be suitable for use in identifying overdose in forensic analysis. [ABSTRACT FROM AUTHOR]

Rationale: The study of insect migration is problematic due to the small size of insects. Stable isotope analysis can be used to elucidate movement, either by geographic assignment of location of a species, or by simply distinguishing migrant from resident populations. There are few isoscapes of any kind in the UK/Ireland available for interrogation. Thus, I have measured stable isotope ratios (of H, C, N and S) of 299 individuals of the non-migratory Brimstone moth (Opisthograptis luteolata) collected from 93 locations around the UK and Ireland by citizen scientists. Methods: After removing lipids, stable isotope ratios were measured by continuous flow isotope ratio mass spectrometry, using either a conventional elemental analyser (C, N and S) or a high-temperature, thermal conversion elemental analyser in reductive mode. Results: Maps (isoscapes) were constructed that illustrate the stable isotope spatial distribution of this insect. These are the first isoscapes of H, C, N and S of biological samples covering both UK and Ireland. Conclusions: The insect isoscape patterns can be explained from what we know of moth diet, climate and geology. Sulfur isotopes may be of particular use for distinguishing individuals from areas of unique geology. Isoscape patterns may (with care) predict isotope compositions of other, herbivorous, non-aquatic, chitinous taxa. Such isoscapes, when extended beyond the UK and Ireland, would provide a useful tool to elucidate insect migration. [ABSTRACT FROM AUTHOR]

Rationale: Stable sulfur isotope compositions (δ34S values) are a useful marker of terrestrial (lower δ34S) versus marine (higher δ34S) diets. In coastal areas, 34S‐enriched sea spray can obscure these marine/terrestrial differences. We sought to establish whether δ34S values of sea spray‐affected terrestrial fauna can be distinguished from those of marine‐feeding terrestrial fauna. Methods: We measured bone and dentine collagen δ34S values, as well as stable carbon (δ13C) and nitrogen (δ15N) isotope compositions via continuous flow elemental analysis/isotope ratio mass spectrometry of 21 sheep (Ovis aries) raised on an island (North Ronaldsay, UK) of <7 km2 that had widely divergent access to marine (seaweed) and heavily sea spray‐affected terrestrial (grass) food sources. We also analyzed the bone collagen of marine and terrestrial fauna from this island. Results: Sheep bone collagen showed well‐defined trends with highly significant correlations between δ13C and δ15N values indicative of feeding along a continuum of fully terrestrial to fully marine diets, consistent with other modern baseline data from marine and terrestrial animals in the same area. In contrast, δ34S values were generally elevated for all sheep and were not significantly correlated with either δ13C or δ15N values. Conclusions: Our findings demonstrate that δ34S values are poorly suited for differentiating marine and terrestrial diets in terrestrial animals in areas with pronounced sea spray effects. Care must be taken to characterize the isotopic compositions of potential food items before δ34S values are used as a marker for reliance on marine protein in modern and ancient contexts. [ABSTRACT FROM AUTHOR]