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Enceladus is an icy moon of Saturn, with a surface composed predominantly of water ice [1]. It has large water vapour plumes, which eject icy grains and volatiles from its subsurface ocean into space [1]. The presence of a subsurface liquid water ocean and evidence of hydrothermal activity in the moon’s interior [2] has made Enceladus a key target in the search for life beyond Earth. Determining the ocean composition is an important consideration in assessing the moon’s habitability, but direct analysis is impossible because it is covered by a thick icy crust [3]. Enceladus’ surface, however, can offer some insights into the processes operating within and on the satellite, but is influenced by several processes that modify its composition. For example, plume material either falls back to the surface of the satellite or is ejected at high enough velocities that it orbits Saturn, forming Saturn's E-ring [4]. Since Enceladus orbits within this structure, E-ring material is redeposited on the surface of the moon. While the distribution and abundance of volatiles deposited by the plumes may be indicative of their presence in the subsurface ocean, E-ring grain deposits have been processed by Saturn’s magnetosphere, experiencing irradiation and erosion in the space environment. Being able to distinguish between volatile profiles of ices from fresh plume material and those subjected to impact by E-ring grains is important for understanding which surface material best represents the ocean composition. To achieve this requires a simulation of impact processes onto Enceladus ices. Ices representative of feasible volatile compositions have been grown in a bespoke cryogenic vacuum system. Ices are grown at temperatures between -95°C and -120°C, at pressures of 10-4 mbar to 10-5 mbar. These conditions have been chosen to best replicate the environment around the Enceladus plumes, without rapidly sublimating the ices at ultra-high vacuum pressures. A Quadrupole Mass Spectrometer (QMS) is used to analyse the composition of the pristine ices prior to impact simulation using the All-Axis Light Gas Gun (LGG) at The Open University. The LGG can achieve hypervelocity impacts at velocities in the range of those predicted for E-ring impact (0.5 km/s to 5 km/s [5, 6, 7]). Salt grains, extracted from simulated E-ring ice particles via sublimation using the cryogenic vacuum system, will be used as projectiles. The volatile profile of impacted Enceladus ice analogues is then analysed using a QMS and compared to the original ices. However, it is critical to understand sources of contamination within the impact simulation, since these may mask modifications that are key to understanding the space weathering processes and invalidate icy impact experiments at low pressures. Any volatile contamination in the headspace of the gun is likely to cryotrap onto the pristine ice analogues and it is expected that, as projectiles are fired, materials used in the shot, such as nylon from the piston and sabot material, will volatilise. Although the chamber is cleaned after each use and nitrogen is used to purge the chamber, the level of contamination from volatilising substances is expected to be high. A QMS has been used to investigate the volatiles within the LGG for the duration of the impact experiments. After the projectiles and shell casing have been loaded and the range of the gun evacuated down to vacuum pressures, the QMS is exposed to the headspace of the small experimental chamber, where targets are placed. It is set up to detect masses between 0 – 200 amu and takes readings throughout the firing process. This includes the initial set up, loading hydrogen in the pump tube, firing the gun, evacuating the range, nitrogen purging, and air purging. The preliminary results indicate that hypervelocity impact studies using Enceladus ice analogues are feasible despite the contamination in the gun and the QMS has proven a valuable method of analysing the headspace of the gun during the firing process. While loading hydrogen in the pump tube in preparation for firing, the results from QMS analysis have shown slight leaks between the pump tube and range (Fig. 1A). This is to be expected as the pump tube is not hermetically sealed from the range, but may be improved upon. It has also shown the presence of higher mass (>100 amu) molecules that are only present for Figure 1. Initial results of the QMS analysis, showing the molecules present at various stages of the firing process. A) shows mass fragments (0-45 amu) in the range of the gun before any shots have been fired, indicative of air. B) shows heavier mass fragments (100-200 amu) detected during the firing process. These peaks are detected at the limits of the QMS sensitivity, which is expected to be why they are detected at the same pressures. References [1] Brown, R. et al. (2006). Composition and physical properties of Enceladus' surface. Science, 311(5766):1425-1428. [2] Hsu, H. et al. (2015) Ongoing hydrothermal activities within Enceladus. Nature, 519(7542):207–210 [3] Cadek, O. et al. (2016) Enceladus’s internal ocean and ice shell constrained from Cassini gravity, shape, and libration data. Geophysical Research Letters, 43(11):5653–5660 [4] Kempf, S. et al. (2010). How the Enceladus dust plume feeds Saturn’s E ring. Icarus, 206(2):446–457 [5] Juhász, A. et al. (2007). Signatures of Enceladus in Saturn’s E ring. Geophysical Research Letters, 34(9) [6] Howett, C. et al. (2018). Ring and Magnetosphere Interactions with Satellite Surfaces. In Enceladus and the Icy Moons of Saturn, pages 343–360. University of Arizona Press [7] Spahn, F., et al. (2006). E- ring dust sources: Implications from Cassini’s dust measurements. Planetary and Space Science, 54(9-10):1024–1032.

Strains of Dunaliella salina microalgae are of considerable research and industrial interest because they hyper-accumulate β-carotene as well as produce high-quality protein. To explore the co-production of valuable compounds in D. salina, this study compared the production of β-carotene, phytoene and amino acids in two strains cultivated under white, red or blue light until no further nitrogen was available. D. salina DF15 (CCAP 19/41 (PLY DF15)) produced more than 12% β-carotene (ash-free dry weight (AFDW) basis), and red light triggered the production of 9-cis β-carotene at a 9-cis/all-trans β-carotene ratio of 1.5. Phytoene production was also evident in D. salina DF15 under all conditions, particularly under blue light. However, the profile of essential amino acids (EAAs) and calculation of the essential amino acid index (EAAI) was less than ideal in terms of protein quality, for both strains. Umami compounds, quantified as monosodium glutamate (MSG) equivalents, indicated a higher equivalent umami concentration (EUC) in D. salina DF15 under red light (3.2 g MSG/100 g AFDW) than in D. salina CCAP19/30. Overall, D. salina DF15 demonstrates valuable traits for further exploration and product optimisation.

IntroductionThe surface of Enceladus could provide one of the best places in our Solar System to investigate the potential for life. Material from plumes seen emanating from Enceladus' South Polar Region[1], which are believed to be sourced directly from the subsurface ocean, is deposited onto the satellite's icy surface[2]. Rapid resurfacing means that material in this area has not been heavily processed by radiation, so could be an excellent indicator of oceanic composition[3, 4]. To date, the only surface species detected with certainty are H2O and CO2[5], with NH3, CH4 and low molecular weight organics tentatively detected[6, 7]. More in depth analysis will only come from future missions to the Saturnian system. The main aim of this work is to develop Enceladus ice analogues of a range of plausible compositions in conditions representative of the surface. The analogues will then be analysed using instrumentation that could be deployed on future missions. A cryogenic vacuum system has been designed in order to replicate the surface environment and grow ices. The analogues grown will be used to test protocols and analytical techniques relevant to future missions. They will then be subjected to simulated space weathering in order to cover all expected possibilities for different surface components and their fate. We will present the preliminary data of the ices grown and the results of testing of the system to ensure it is operating at optimum conditions. MethodsIn order to grow and analyse ices in conditions representative of Enceladus' surface, a vacuum chamber, previously used for analysis of pure H2O ice for the development of the Lunar Volatiles Mobile Instrumentation (LUVMI) rover[8], was repurposed. The chamber has a 35 L capacity and two vacuum pumps that can achieve internal pressures of 10-7 mbar. The chamber is also fitted with ports to allow it to be connected to analysis equipment such as a GC-MS. The analogues are grown within a sample holder made out of copper piping wrapped around a copper cooling plate. Liquid nitrogen is injected into the chamber and flows through the piping to cool it down to temperatures of -140 °C. Gas mixtures are injected into the chamber, so that they are condensed onto the cold sample holder and form ices. The system is currently undergoing preliminary calibration and testing in order to optimise operating procedures. H2O and H2O-salt mixtures will be inserted into the sample holder as liquids, then cooled and frozen, before the gas mixtures are inserted. A table showing the preliminary ice mixing ratios can be seen in Table 1. These preliminary compositions are based on upper limits estimated for surface components[5, 7, 9, 10]. The ices grown will be analysed initially using a GC-MS in order to fully characterise both them and the cryogenic system. Table 1. Expected mixing ratios for ices Mixing Ratio Surface Component Ice 1 Ice 2 Ice 3 Ice 4 H2O 99% 98% 98% 96% CO2 1% 1% 1% 1% NH3 - 2% 2% 1.5% CH4 - - 2% 1% NaCl - - - 0.5% Currently, the main system has the capabilities to be connected to a GC-MS, but in order to preserve the ices while in transport to other pieces of equipment for further experiments, an additional system is required. This system is in development, and is designed to replicate a perfect sample oven onboard a spacecraft. A series of valves connects to an external mini chamber, which is capable of being removed from the main system. Within the mini chamber, the sample holder is connected to an external copper bar, which is submerged in liquid nitrogen in order to cool the samples. This allows the ices to be kept in relatively pristine conditions over a longer period of time while being transported. The effects of thermal and vacuum leaks on the ices within the chamber will be determined, in order to mimic potential issues with sample handling onboard a lander. The preliminary results of ice analogue development, including physical and compositional characterisation, will be presented. In addition, the limitations of the system and how potential instrumentation issues during a mission could affect Enceladus ices will also be presented. Future work will include investigating the effects of space weathering on the ices and their subsequent analysis. The main focus will be on impacts that are representative of E-ring grains colliding with the surface and will be investigated using a Van de Graaff Dust Accelerator. References [1] Porco, C et al. (2006) Science 311 1393-1401 [2] Kempf, S et al. (2018) Enceladus and the icy moons of Saturn 195-210 [3] Kempf, S et al. (2008) Icarus 193 420-437 [4] Howett, C et al. (2018) Enceladus and the icy moons of Saturn 342-360 [5] Brown, R et al. (2006) Science 311 1425-1428 [6] Brown, R et al. (2004) Space Science Reviews 115 111-168 [7] Waite, J et al. (2006) Science 311 1419-1422 [8] Gancet, J et al. (2017) 13th Symposium on Advanced Space Technologies in Robotics and Automation 1-8 [9] Emery, J et al. (2005) Astronomy & Astrophysics 435 353-362 [10] Postberg, F et al. (2009) Nature 459 1098-1101

Anti-doping analysis requires an exceptional level of accuracy and precision given the stakes that are at play. Current methods rely on the application of chromatographic techniques linked with mass spectrometry to provide this. However, despite the effectiveness of these techniques in achieving good selectivity and specificity, some issues still exist. In order to reach the minimum required performance level as set by WADA, labs commonly use selective monitoring by quadrupole mass spectrometry. This can be potentially fooled through the use of masking agents or by moving the peaks, as often only a small portion of the spectrum is used for analysis. Further issues exist in the inability to detect new or modified compounds, or to reanalyse samples/spectra. One technique that could overcome these problems is that of comprehensive 2D chromatography. Here a second separation column is employed to generate greater separative power. Compared to conventional separation, GCxGC allows for a greater peak capacity (i.e., number of peaks that can be resolved within a given time) and greater separation of coeluting compounds, which makes the technique promising for the complex task required in anti-doping. When combined with Time of Flight Mass Spectrometry this technique demonstrates vast potential allowing for full mass range datasets to be obtained for retroactive analysis. Similarly, LCxLC provides improvements in resolving power compared to its 1D counterpart and can be used both online as part of the analysis or offline solely as a purification step. In this review we summarise the work in this field so far, how comprehensive chromatography has been applied to anti-doping studies, and discuss the future application for this technique.

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link. The problem posed by anti-doping requirements is one of the great analytical challenges; multiple compound detection at low ng ml−1 levels from complex samples, with requirements for exceptional confidence in results. This review surveys the design, synthesis and application of molecularly imprinted polymers (MIPs) in this field, focusing on the templating of androgenous anabolic steroids (AASs), as the most commonly abused substances, but also other WADA prohibited substances. Commentary on the application of these materials in detection, clean-up and sensing is offered, alongside views on the future of imprinting in this field.

Biologics are an integral component in the treatment of various diseases. However, limited patient access to these medicines remains a significant global challenge, prompting development of safe and effective biosimilars. A biosimilar is 'highly similar to a reference (originator) product, for which there are no clinically meaningful differences between the two products in terms of safety, purity and potency'. Biosimilars have the potential to offer possible benefits, including lower treatment costs, thereby increasing patient access and clinical use, which may lead to better overall outcomes. Improved understanding of biosimilars may enhance confidence and trust in these agents. As increasing numbers of biosimilars achieve regulatory approval, this overview aims to address enduring knowledge gaps regarding the development and use of biosimilars. ispartof: FUTURE ONCOLOGY vol:15 issue:7 pages:777-790 ispartof: location:England status: published

Ptolemy is a Gas Chromatograph–Isotope Ratio–Mass Spectrometer (GC–IR–MS) aboard the Philae lander element of the Rosetta mission to comet 67P/Churyumov-Gerasimenko. Developed to determine the chemical and stable light isotopic composition of cometary material, Ptolemy was conceived as a highly flexible instrument able to accommodate changes in operational functionality via software modification. This was considered essential to allow for different modes of operation not only in response to rapid/unexpected changes and opportunities, but also to longer-term shifts in priorities as the overall mission plan (and indeed cometary science in general) changed during the decades from initial concept to landing. Against the backdrop of events of the Philae landing, this paper describes the methods of instrument operation and rational behind them used to achieve the Ptolemy scientific results during the period 12–14th November 2014. In particular we demonstrate the importance of a flexible modular approach to the instrument architecture enabling complex instrument operations, especially in a situation where the environment of exploration is effectively unknown and some of the engineering solutions were being tested in the field for the first time.

Background: Results of small trials indicate that fluoxetine might improve functional outcomes after stroke. The FOCUS trial aimed to provide a precise estimate of these effects.Methods: FOCUS was a pragmatic, multicentre, parallel group, double-blind, randomised, placebo-controlled trial done at 103 hospitals in the UK. Patients were eligible if they were aged 18 years or older, had a clinical stroke diagnosis, were enrolled and randomly assigned between 2 days and 15 days after onset, and had focal neurological deficits. Patients were randomly allocated fluoxetine 20 mg or matching placebo orally once daily for 6 months via a web-based system by use of a minimisation algorithm. The primary outcome was functional status, measured with the modified Rankin Scale (mRS), at 6 months. Patients, carers, health-care staff, and the trial team were masked to treatment allocation. Functional status was assessed at 6 months and 12 months after randomisation. Patients were analysed according to their treatment allocation. This trial is registered with the ISRCTN registry, number ISRCTN83290762.Findings: Between Sept 10, 2012, and March 31, 2017, 3127 patients were recruited. 1564 patients were allocated fluoxetine and 1563 allocated placebo. mRS data at 6 months were available for 1553 (99·3%) patients in each treatment group. The distribution across mRS categories at 6 months was similar in the fluoxetine and placebo groups (common odds ratio adjusted for minimisation variables 0·951 [95% CI 0·839–1·079]; p=0·439). Patients allocated fluoxetine were less likely than those allocated placebo to develop new depression by 6 months (210 [13·43%] patients vs 269 [17·21%]; difference 3·78% [95% CI 1·26–6·30]; p=0·0033), but they had more bone fractures (45 [2·88%] vs 23 [1·47%]; difference 1·41% [95% CI 0·38–2·43]; p=0·0070). There were no significant differences in any other event at 6 or 12 months.Interpretation: Fluoxetine 20 mg given daily for 6 months after acute stroke does not seem to improve functional outcomes. Although the treatment reduced the occurrence of depression, it increased the frequency of bone fractures. These results do not support the routine use of fluoxetine either for the prevention of post-stroke depression or to promote recovery of function.Funding: UK Stroke Association and NIHR Health Technology Assessment Programme.

Evolved gas analysis (EGA) has been successfully applied to the studies of meteorites and Apollo lunar samples. It consists of linear heating of a material with registration of the released volatile compounds, typically using a spectrometric technique. However, so far no quantitative comparison was possible of the amount of gases released during heating of a sample. To address this limitation, we have developed a Quantitative EGA (QEGA) technique using our custom-built Finesse mass spectrometry system. It is based on calibration of the quadrupole mass spectrometer with reference gases (e.g. CO2, CO, H2, O2, N2 or their mixtures with known relative abundances) with known flow rate. The method was tested using simple chemical compounds such as CaCO3, which give well-known amounts of pure gases during their thermal decomposition. We present initial QEGA data on two reference meteorites, Allende and Murchison. Our QEGA work is also informing the design and operation of ProSPA spaceflight instruments being developed to perform analogous experiments in situ on the lunar surface through the European Space Agency's PROSPECT payload on Luna 27.

Previous studies have indicated that volatile organic compounds specific to bladder cancer may exist in urine headspace, raising the possibility that they may be of diagnostic value for this particular cancer. To further examine this hypothesis, urine samples were collected from patients diagnosed with either bladder cancer or a non‐cancerous urological disease/infection, and from healthy volunteers, from which the volatile metabolomes were analysed using gas chromatography mass spectrometry. The acquired data were subjected to a specifically designed pattern recognition algorithm, involving cross‐model validation. The best diagnostic performance, achieved with independent test data provided by healthy volunteers and bladder cancer patients, was 89% overall accuracy (90% sensitivity and 88% specificity). Permutation tests showed that these were statistically significant, providing further evidence of the potential for volatile biomarkers to form the basis of a non‐invasive diagnostic technique.

Highlights • We developed a sample clean-up method to detect tuberculosis from sputum by GC–MS. • Biomarkers recovered: 64–70% (standards solution), and 36–68% (sputum extracts). • Cholesterol removed: 93–98% (standards solution) and 62–92% (sputum extracts). • Less cholesterol in the filtered extracts avoids overloading of the analytical system. • Analyzing large sample batches will need fewer interruptions for system cleaning., A proof of principle gas chromatography–mass spectrometry method is presented, in combination with clean up assays, aiming to improve the analysis of methyl mycocerosate tuberculosis biomarkers from sputum. Methyl mycocerosates are generated from the transesterification of phthiocerol dimycocerosates (PDIMs), extracted in petroleum ether from sputum of tuberculosis suspect patients. When a high matrix background is present in the sputum extracts, the identification of the chromatographic peaks corresponding to the methyl derivatives of PDIMs analytes may be hindered by the closely eluting methyl ether of cholesterol, usually an abundant matrix constituent frequently present in sputum samples. The purification procedures involving solid phase extraction (SPE) based methods with both commercial Isolute-Florisil cartridges, and purpose designed molecularly imprinted polymeric materials (MIPs), resulted in cleaner chromatograms, while the mycocerosates are still present. The clean-up performed on solutions of PDIMs and cholesterol standards in petroleum ether show that, depending on the solvent mix and on the type of SPE used, the recovery of PDIMs is between 64 and 70%, whilst most of the cholesterol is removed from the system. When applied to petroleum ether extracts from representative sputum samples, the clean-up procedures resulted in recoveries of 36–68% for PDIMs, allowing some superior detection of the target analytes.

A MEMS-based gas chromatograph (GC) front-end for a mass spectrometer has been developed for space applications. The GC uses Molecular Vapor Deposition (MVD) to achieve a uniform coating of the GC column. Particular attention has been paid to the fluidic connections of the MEMS to the external tubing.

The September 5th 2008 Rosetta flyby of asteroid 2867 Steins raised tantalising questions concerning the possibility of outgassing and extant exospheres surrounding small bodies within the asteroid belt. With this in mind and recognising the size and composition of asteroid 21 Lutetia it was decided to attempt a detection of such possible outgassing using a number of Rosetta instruments, including Ptolemy, a miniature gas chromatograph isotope ratio mass spectrometer aboard the lander Philae. Ptolemy collected 5 sets of mass spectra at hourly intervals during the Lutetia encounter; 2 background measurements either side of close approach and an exosphere detection measurement as the spacecraft passed over the subsolar point. An increase in pressure was detected at the subsolar point but the cause (exosphere or spacecraft) was unresolved with the realisation that any such detection is hindered by outgassing from the spacecraft and instrument itself. Constraints are placed on the properties of Lutetia exosphere, structure and production rates. The experience gained is used to provide suggestions for future missions or spacecraft events aimed at the detection and characterisation of the exospheres of Solar System bodies.

A novel ionisation source which uses commercially available Carbon Nano Tube devices is demonstrated as a replacement for a filament based ionisation source in an ion trap mass spectrometer. The carbon nanotube ion source electron emission was characterised and exhibited typical emission of 30 ± 1.7 μA with an applied voltage differential of 300 V between the carbon nanotube tips and the extraction grid. The ion source was tested for longevity and operated under a condition of continuous emission for a period of 44 h; there was an observed reduction in emission current of 26.5% during operation. Spectra were generated by installing the ion source into a Finnigan Mat ITD700 ion trap mass spectrometer; the spectra recorded showed all of the characteristic m/z peaks from m/z 69 to m/z 219. Perfluorotributylamine spectra were collected and averaged contiguously for a period of 48 h with no significant signal loss or peak mass allocation shift. The low power requirements and low mass of this novel ionisation source are considered be of great value to future space missions where mass spectrometric technology will be employed.

On November 12, 2014, the ESA/Rosetta descent module Philae landed on the Abydos site of comet 67P/Churyumov-Gerasimenko. Aboard this module, the Ptolemy mass spectrometer measured a CO/CO2 ratio of 0.07 +/- 0.04 which differs substantially from the value obtained in the coma by the Rosetta/ROSINA instrument, suggesting a heterogeneity in the comet nucleus. To understand this difference, we investigated the physico-chemical properties of the Abydos subsurface leading to CO/CO2 ratios close to that observed by Ptolemy at the surface of this region. We used a comet nucleus model that takes into account different water ice phase changes (amorphous ice, crystalline ice and clathrates), as well as diffusion of molecules throughout the pores of the matrix. The input parameters of the model were optimized for the Abydos site and the ROSINA CO/CO2 measured ratio is assumed to correspond to the bulk value in the nucleus. We find that all considered structures of water ice are able to reproduce the Ptolemy observation with a time difference not exceeding ~50 days, i.e. lower than ~2% on 67P/Churyumov-Gerasimenko's orbital period. The suspected heterogeneity of 67P/Churyumov-Gerasimenko's nucleus is also found possible only if it is constituted of crystalline ices. If the icy phase is made of amorphous ice or clathrates, the difference between Ptolemy and ROSINA's measurements would rather originate from the spatial variations in illumination on the nucleus surface. An eventual new measurement of the CO/CO2 ratio at Abydos by Ptolemy could be decisive to distinguish between the three water ice structures., Comment: 5 pages, 5 figures - Accepted for publication in The Astrophysical Journal

The surface and subsurface of comets preserve material from the formation of the solar system. The properties of cometary material thus provide insight into the physical and chemical conditions during their formation. We present mass spectra taken by the Ptolemy instrument 20 minutes after the initial touchdown of the Philae lander on the surface of comet 67P/Churyumov-Gerasimenko. Regular mass distributions indicate the presence of a sequence of compounds with additional -CH 2 - and -O- groups (mass/charge ratios 14 and 16, respectively). Similarities with the detected coma species of comet Halley suggest the presence of a radiation-induced polymer at the surface. Ptolemy measurements also indicate an apparent absence of aromatic compounds such as benzene, a lack of sulfur-bearing species, and very low concentrations of nitrogenous material.

A fundamental goal of cometary studies is to determine the exact relationship between these bodies and the Solar System – the question(s) can be summarised as follows: did comets originate during the same events that spawned the Sun and planets, are they more primitive bodies that record a pre-solar history, or are they interstellar materials collected in relatively more recent times? Now, whatever the origin of comets, it is entirely possible that they could, in part, contain interstellar or pre-solar components – indeed, it seems rather likely in light of the fact that primitive meteorites contain such entities. These particular components are likely to be refractory (dust, macromolecular organic complexes, etc.). Of more relevance to the issues above are the volatile constituents, which make up the bulk of a comet's mass. Since these materials, by their very nature, volatilise during perihelion passage of a comet they can, in some instances, be detected and measured spectroscopically. Perhaps the most useful species for isotopic investigations are C2, HCN and CN. Unfortunately, spectroscopic measurements can only currently be made with accuracies of ±10 to ±20%. As such it is very often not practical to conclude anything further than the fact that isotopic measurements are compatible with ‘`solar’' values, which tends to imply an origin from the margins of the solar accretion disk. But there is another problem with the spectroscopic measurements – since these are made on gaseous species in the coma (and relatively minor species at that) it is impossible to be certain that these represent the true nuclear values. In other words, if the processes of sublimation, active jetting, and photochemistry in the coma impart isotopic fractionation, the spectroscopic measurements could give a false impression of the true isotope ratios. What is required is an experiment capable of measuring isotopic ratios at the very surface of a comet. Herein we describe the Ptolemy instrument, which is included on the Philae lander as part of the Rosetta mission to 67P/Churyumov-Gerasimenko. The major objective of Ptolemy is a detailed appraisal of the nature and isotopic compositions of all materials present at the surface of a comet.

The Ptolemy instrument on the Philae lander (of the Rosetta space mission) was able to make measurements of the major volatiles, water, carbon monoxide and carbon dioxide, directly at the surface of comet 67P/Churyumov–Gerasimenko. We give some background to the mission and highlight those instruments that have already given insights into the notion of water in comets, and which will continue to do so as more results are either acquired or more fully interpreted. On the basis of our results, we show how comets may in fact be heterogeneous over their surface, and how surface measurements can be used in a quest to comprehend the daily cycles of processes that affect the evolution of comets. This article is part of the themed issue ‘The origin, history and role of water in the evolution of the inner Solar System’.

The author's final peer reviewed version can be found by following the URI link. The Publisher's final version can be found by following the DOI link. method capable of screening for multiple steroids in urine has been developed, using a series of twelve structurally similar, and commercially relevant compounds as target analytes. A molecularly imprinted solid phase extraction clean-up step was used to make the sample suitable for injection onto a GC×GC-MS setup. Significant improvements compared to a commercially available C-18 material were observed. Each individual steroid was able to be separated and identified, using both the retention profile and diagnostic fragmentation ion monitoring abilities of the comprehensive chromatographic-mass spectrometry method. Effective LODs of between 11.7 and 27.0 pg were calculated for individual steroids, effectively equivalent to concentration levels of between 0.234 and 0.540 ng mL−1 in urine, while the application of multiple screen was demonstrated using a 10 ng mL−1 mixed sample. The nature of this study also removes the need for sample derivitisation which speeds up the screening process.

Global budgets of atmospheric trace gases are increasingly being constrained by means of stable isotope measurements. Published analytical techniques for studying the parallel stable isotopic composition of methane (delta(13)C and deltaD) require prohibitively large quantities of methane for analysis, making them unsuitable for studies where sample size is small, e.g. soil methane fluxes. A highly sensitive static mass spectrometer has been developed which uniquely uses CH(4) as the analyte. The method requires only 8 ng of CH(4) for analysis (

RATIONALE The phthiocerol dimycocerosates (PDIMs) are certain stable and hydrophobic waxes found in the cell membrane of Mycobacterium tuberculosis, bacteria that cause an infectious disease of growing concern worldwide. Previous studies report the analysis of derivatives of the hydrolysed PDIMs from biological samples, following complex extraction and offline derivatization of PDIMs biomarkers, prior to their analysis by gas chromatography/mass spectrometry (GC/MS). METHODS We developed and optimized a GC/MS method based on selected ion monitoring (SIM) to detect the derivatives produced via the thermally assisted hydrolysis and methylation (THM) of the PDIMs from the cell membrane of M. tuberculosis. The extraction of PDIMs from culture is simple, and their thermochemolysis is carried out automatically online, thus avoiding the time-consuming derivatization steps of hydrolysis and esterification, usually performed offline. RESULTS For standard PDIMs in petroleum ether, our optimized method gave an excellent linearity (R2 = 0.99) at concentrations between 0.172 and 27.5 ng/mL, a good precision (RSD = 11.42 %), and a limit of detection (LOD) of 100 pg/mL. For the PDIMs extracted from dilutions of M. tuberculosis culture, the method gave good linearity (R2 = 0.9685) and an estimated LOD of 400 CFU/mL (CFU = colony forming units) in sterile distilled water. CONCLUSIONS A GC/MS(SIM) method is presented for the rapid and quantitative detection of M. tuberculosis, based on the online thermochemolysis of lipidic biomarkers extracted from the bacterial culture. The method has the potential to be applied in human and veterinary clinical laboratories for the rapid diagnosis of tuberculosis in infected biological samples. © 2013 The Authors. Rapid Communications in Mass Spectrometry published by John Wiley & Sons, Ltd.

Tuberculosis requires rapid diagnosis to prevent further transmission and allow prompt administration of treatment. Current methods for diagnosing pulmonary tuberculosis lack sensitivity are expensive or are extremely slow. The identification of lipids using gas chromatography- electron impact mass spectrometry (GC-EI/MS) could provide an alternative solution. We have studied mycocerosic acid components of the phthiocerol dimycocerosate (PDIM) family of lipids using thermochemolysis GC-EI/MS. To facilitate use of the technology in a routine diagnostic laboratory a simple extraction procedure was employed where PDIMs were extracted from sputum using petroleum ether, a solvent of low polarity. We also investigated a method using methanolic tetramethylammonium hydroxide, which facilitates direct transesterification of acidic components to methyl esters in the inlet of the GC-MS system. This eliminates conventional chemical manipulations allowing rapid and convenient analysis of samples. When applied to an initial set of 40 sputum samples, interpretable results were obtained for 35 samples with a sensitivity relative to culture of 94% (95%CI: 69.2,100) and a specificity of 100% (95%CI: 78.1,100). However, blinded testing of a larger set of 395 sputum samples found the assay to have a sensitivity of 61.3% (95%CI: 54.9,67.3) and a specificity of 70.6% (95%CI: 62.3,77.8) when compared to culture. Using the results obtained we developed an improved set of classification criteria, which when applied in a blinded re-analysis increased the sensitivity and specificity of the assay to 64.9% (95%CI: 58.6,70.8) and 76.2% (95%CI: 68.2,82.8) respectively. Highly variable levels of background signal were observed from individual sputum samples that inhibited interpretation of the data. The diagnostic potential of using thermochemolytic GC-EI/MS of PDIM biomarkers for diagnosis of tuberculosis in sputum has been established; however, further refinements in sample processing are required to enhance the sensitivity and robustness of the test.

A technique using comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GCxGC/TOFMS) is applied to a qualitative analysis of three sample extracts from hair suspected of containing various drug compounds. The samples were also subjected to a quantitative target analysis for codeine, morphine, 6-monoacetylmorphine (6-MAM), amphetamine, methamphetamine, methylenedioxyamphetamine (MDA), methylenedioxymethylamphetamine (MDMA), methadone, and benzylpiperazine (BZP) by liquid chromatography-tandem mass spectrometry (LC-MS/MS). GCxGC/TOFMS provided a non-specific procedure that identified various drugs, metabolites, and impurities not included in the target analysis. They included cocaine, diazepam, and methaqualone (quaalude). Comprehensive GCxGC separation was achieved using twin-stage cryo-modulation to focus eluant from a DB-5 ms (5% phenyl) to a BPX50 (50% phenyl) GC column. The TOF mass spectrometer provided unit mass resolution in the mass range m/z 5-1000 and rapid spectral acquisition (≤500 spectra/s). Clean mass spectra of the individual components were obtained using mass spectral deconvolution software. The 'unknown' components were identified by comparison with mass spectra stored in a library database

The paper presents the application of a method based on coupled gas chromatography-mass spectrometry, using an isotopically labelled internal standard for the quantitative analysis of benzene (B), toluene (T), ethyl benzene (E), and o-, m-, p-xylenes (X). Their atmospheric concentrations were determined based on short-term sampling, in different sites of Cluj-Napoca, a highly populated urban centre in N-W Romania, with numerous and diversified road vehicles with internal combustion engines. The method is relatively inexpensive and simple and shows good precision and linearity in the ranges of 7–60μg/m3(B), 13–90μg/m3(T), 7–50μg/m3(E), 10–70μg/m3(X-m,p), and 20–130μg/m3(X-o). The limits of quantitation/detection of the method LOQ/LOD are of 10/5μg/m3(Xo), 5/3μg/m3(B, E, X-m,p), and of 3/1μg/m3(T), respectively.

A technique using comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GC × GC/TOFMS) is applied to qualitative and quantitative drug testing. Human serum was ‘spiked’ with known quantities of benzodiazepines and a ‘street heroin’ mixture including some of the major metabolites and impurities. The sample components were extracted from the matrix by solid-phase extraction (SPE). Constituents containing polar hydroxyl and/or secondary amine groups were derivatised with N-methyl-N-(tert-butyldimethyl)trifluoroacetamide (MTBSTFA) to improve the chromatographic performance. An orthogonal separation of the matrix constituents was achieved by coupling a DB-5ms (5% phenyl) to a BPX50 (50% phenyl) GC column. The eluant was focused onto the second column by a twin-stage cryo-modulator. Rapid 6 s modulation times were achieved by transfer from a 30 m × 0.25 mm (length × internal diameter) to a 2 m × 0.1 mm column. TOFMS with rapid spectral acquisition (≤500 spectra/s) was employed in the mass range m/z 40–650. A clean mass spectrum was obtained for each analyte using mass spectral deconvolution software. The sensitivity and repeatability of the method were evaluated by the preparation of calibration standards for two benzodiazepines, flunitrazepam and its major metabolite 7-aminoflunitrazepam (7-amino-FN), in the concentration range 5–1000 ng/mL. The limits of detection (LODs) and limits of quantitation (LOQs), calculated by repeat injections (×10) of the lowest standard, were 1.6 and 5.4 ng/mL (flunitrazepam); 2.5 and 8.5 ng/mL (7-amino-FN), respectively. There is scope to extend this protocol to screen a large number of drugs and metabolites stored in a library database. Copyright © 2009 John Wiley & Sons, Ltd.

Plants are a major atmospheric source of volatile organic compounds (VOCs). These secondary metabolic products protect plants from high-temperature stress, mediate in plant–plant and plant–insect communication, and affect our climate globally. The main challenges in plant foliar VOC research are accurate sampling, the inherent reactivity of some VOC compounds that makes them hard to detect directly, and their low concentrations. Plant VOC research relies on analytical techniques for trace gas analysis, usually based on gas chromatography and soft chemical ionization mass spectrometry. Until now, these techniques (especially the latter one) have been developed and used primarily by physicists and analytical scientists, who have used them in a wide range of scientific research areas (e.g., aroma, disease biomarkers, hazardous compound detection, atmospheric chemistry). The interdisciplinary nature of plant foliar VOC research has recently attracted the attention of biologists, bringing them into the field of applied environmental analytical sciences. In this paper, we review the sampling methods and available analytical techniques used in plant foliar VOC research to provide a comprehensive resource that will allow biologists moving into the field to choose the most appropriate approach for their studies.

In May 2014, the Rosetta spacecraft is scheduled to rendezvous with the comet Churyumov-Gerasimenko ('67P'). One of the instruments on board the 'Lander' which will descend on to the surface of the comet is a miniaturised GC/MS system that incorporates an ion trap mass spectrometer, specially developed for isotope ratio analysis. This article describes the development and optimisation of the ion trap for this unique application, and presents a summary of the range of pre-programmed experiments that will contribute to the characterisation of the solid and volatile cometary materials.

An appeal for witnesses to a fireball on 24 September produced an excellent response from the public; 55 eyewitnesses sent accounts. From their observations we calculated the radiant azimuth as 320degrees, and altitude,angle less than or equal to 20degrees. Without video or CCTV footage for control on the fireball's velocity or pre-entry orbit, we used software developed for dust impact experiments, to assess the most likely orbital trajectory. The highest probability solutions have a semimajor axis between 1.6 and 2.0 AU and an eccentricity of 0.4 to 0.5, corresponding to a typical near-Earth asteroid orbit. Of possible comet showers, the kappa Aquarids are within the calculated constraints. No fragments were found, despite considerable public interest, consistent with the absence of reports of a dust trail. Public response to this fireball demonstrates the great interest in meteoritic phenomena, particularly when, as in this case, participation in the scientific enquiry is actively encouraged.

The instrumentation on the 60 kg Beagle 2 lander for ESA's 2003 Mars Express mission will be described. Beagle 2 will be search for organic material on and below the surface of Mars in addition to a study of the inorganic chemistry and mineralogy of the landing site. The lander will utilize acquisitions and preparation tools to obtain samples from below the surface, and both under and inside rocks. In situ analysis will include examination of samples with an optical microscope, Mossbauer and fluorescent X-ray spectrometers. Extracted samples will be returned to the lander for analysis, in particular a search for organics and a measurement of their isotopic composition. The experiment configuration and design will be described along with the status of the project.

The 60 kg Beagle 2 lander for ESA's 2003 Mars Express mission will be described. Beagle 2 will search for organic material on and below the surface of Mars in addition to a study of the inorganic chemistry and mineralogy of the landing site. The lander will utilize a mechanical mole and grinder to obtain samples from below the surface, under rocks, and inside rocks. Such samples will be returned to the lander for detailed analysis. Analysis will include examination of samples and rocks and soils with an optical microscope and X-ray Spectrometer and Mossbauer Spectrometers as well as a search for organics and a measurement of their isotopic composition. The lander systems design as well as the experiment configuration will be described along with the status of the project.

The weakness of the Hobbesian sovereign which arises out of what the individual can do in his own defence is well established. What has not been examined is the attempts Hobbes makes to counter this and that is the concern of this article. He appeals to the individual to exercise caution on three distinct grounds: on grounds of gallantry, on grounds of ‘reasonability’ and finally by reference to theology. Each appeal is examined and each is seen to fail. Such is Hobbes's insistence on Passion and Will as the basis of society that he finds it impossible to appeal to Reason and Nature to temper its exercise.