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We present the analysis of a 2.06 Ga apatite crystal obtained from an ultramafic phoscorite rock from the Phalaborwa Complex (Limpopo Province, South Africa) [1]. A space-prototype laser ablation ionisation mass spectrometer (LIMS) [2,3] was used to study the chemical composition of the sample. Mass spectra were recorded from a sample area of 0.6x0.6 mm2, with a spatial resolution of 30 μm and sub-micrometre depth resolution.Apatite is a calcium phosphate mineral expressed by the chemical stoichiometric formula [Ca5(PO4)3(F, Cl, OH)]. The halogen site, occupied by F, Cl, and OH, corresponds to an isomorpous series with fluor-, chlor- and hydroxyl-apatite end members, respectively. Apatite, being an accessory mineral in igneous and other rocks, commonly contains a range of other elements that do not fit well into the major rock forming minerals, such as rare earth elements (REE). These are suitable targets for investigating physical and chemical conditions in igneous rocks and the volatile evolution of magmas.The analysis of the spectra recorded with our LIMS system for the abundances of the elements of interest at each location were performed in two steps. First, the abundances of each element across the sampled area were compiled in element maps. And second, an unsupervised machine learning algorithm based on clustering and network analysis was applied to the data set of analysed mass spectra to separate it into groups of distinct chemical composition. Subsequently, a more detailed analysis was conducted on each of the recovered groups to assign the corresponding mineral. In addition to the group of spectra belonging to apatite, which was assigned to fluorapatite, other minerals were identified, amongst others olivine. This method yields an unsupervised approach to identify different mineralogical entities present within a sample. This network analysis method was previously applied to a 1.88 Ga Gunflint sample (Ontario, Canada) to separate spectra recorded from the host (chert) from spectra containing signatures of organic matter from fossilized microbes [4].Given that the data were recorded using a miniature mass spectrometer designed for space flight, this analysis demonstrates the analytical capabilities of our LIMS system that could be achieved in-situ on other planetary bodies in our Solar System, for example on the Moon or on Mars. The current performance of this miniature LIMS instrument to study the chemical composition of apatite is sufficiently high to measure volatiles (H, F, Cl) and nearly all relevant mineral and partially trace elements (Na, C, Mg, Si, S, K, Mn, Fe, Sr, Ba), including REE (La, Ce, Pr, Sm) which allows for a systematic quantitative analysis of their distribution.[1] Tulej, M. et al., 2022, https://doi.org/10.3390/universe8080410.[2] Riedo, A. et al., 2012, https://doi.org/10.1002/jms.3104.[3] Tulej, M. et al., 2021, https://doi.org/10.3390/app11062562.[4] Lukmanov, R.A. et al., 2022, https://doi.org/10.3389/frspt.2022.718943

Direct analysis of micrometer-scale features embedded in solid samples of a wide chemical variety is an integral part of many fields in geo-, geobio-, and planetary sciences. Examples range from microscopic mineral inclusions in meteoritic material, (e.g., zircons, CAIs, chondrules, etc.) to biological inclusions in a variety of mineralogical host materials, e.g., (putative) fossils of microbial species. In many of these use-cases, the determination of the element and/or isotope composition, specifically those of minor or trace abundance, is of prime interest, meaning mass spectrometry is typically the preferred analysis technique.As a result, a growing group of instruments has been (and are being) developed specifically with the purpose of element and/or isotope analysis of microscale features in solid hosts, each with its specific advantages and limitations. Perhaps the most well-known technique is (nano)SIMS, which boasts analysis spot sizes down to the nanometer level as well as ppm to ppb detection limits, but struggles with quantitativeness and capital and operating expenses. In the field of laser-based solid sampling mass spectrometric techniques, LA-ICP-MS has become a well-established technique, mainly due to its reproducibility and ease of operation. However, due to necessity to transport particles from the ablation plume to the ICP, this technique is inherently limited through fractionation effects and isobaric interferences with the plasma and carrier gas. Furthermore, sample dilution in the plasma and the subsequent loss of sample at the ICP-MS interface result in diminished limits of detection.Another member of the laser-based solid sampling techniques is Laser Ablation Ionization Mass Spectrometry (LIMS), in which the ions present in the ablation plume are directly introduced into the mass spectrometer. This direct sampling of the ablation plume results in both a significant advantage over LA-ICP-MS (high sensitivity) and a challenge (mass resolution). The limited mass resolution of typical LIMS instruments often makes (quantitative) analysis challenging due to isobaric interferences, especially when applied to more complex materials. To solve this issue, the Laser Mass Spectrometer – Gran Turismo (LMS-GT) was developed at the University of Bern with the aim of achieving mass resolutions sufficient to resolve the most common isobaric interferences (M/ΔM = 10.000).Over the last years, commissioning and continuous improvement of the instrument has been ongoing, which has led to a set of analytical performance characteristics which highlight the potential complementary value of LMS-GT. In this talk, we will discuss the latest technological developments1, latest analytical performance metrics (mass resolution, mass accuracy, limits of detection, etc.), and element and isotope ratio accuracies2,3. We will also discuss a case-study in which LMS-GT was used to study fossilized microbial inclusions in Gunflint chert4, highlighting both the potential strength and challenges for LMS-GT in a geo- and geobiosciences context.1. Gruchola, S. et al., Int. J. Mass Spectrom. 474, 116803 (2022).2. Wiesendanger, R. et al., J. Anal. At. Spectrom. 34, 2061–2073 (2019).3. de Koning, C. P. et al., Int. J. Mass Spectrom. 470, 116662 (2021).4. Lukmanov, R. A. et al., Front. Space Technol. 3, (2022).

We present chemical depth profiling studies on mineralogical inclusions embedded in amygdale calcium carbonate by our Laser Ablation Ionisation Mass Spectrometer designed for in situ space research. An IR femtosecond laser ablation is employed to generate ions that are recorded by a miniature time-of-flight mass spectrometer. The mass spectra were measured at several locations on the sample surface and yield chemical depth profiles along the depth length of about 30 mm. The presence of oxides and sulphides within inclusion material allows us to derive elemental abundance calibration factors (relative sensitivity coefficients, RSCs) for major and minor elements. These are obtained from the atomic intensity correlations performed on the depth profiling data. With the RSCs corrections the quantitative analysis of more complex mineralogical phases within the inclusion is conducted by correlating atomic abundance fractions in ternary diagrams, typically used in geology. The spatial resolution of the depth profiles was sufficient to study chemically distinct micrometre-sized objects, such as mineralogical grains and thin layers of minerals including micrometre-sized filamentous structures. The method presented here is well-suited for the quantitative chemical analyses of highly heterogeneous materials where the ablation condition can vary locally with the material composition making the application of standard reference materials less accurate. The presented method is developed to distinguish between abiotic and biological material while searching for micrometre-sized extinct or extent life forms on the surfaces of Solar System bodies.

In this contribution, we investigated the chemical composition of Precambrian microfossils from the Gunflint chert (1.88 Ga) using a miniature laser ablation ionization mass spectrometer (LIMS) developed for in situ space applications. Spatially resolved mass spectrometric imaging (MSI) and depth profiling resulted in the acquisition of 68,500 mass spectra. Using single mass unit spectral decomposition and multivariate data analysis techniques, we identified the location of aggregations of microfossils and surrounding inorganic host mineral. Our results show that microfossils have unique chemical compositions that can be distinguished from the inorganic chert with high fidelity. Chemical depth profiling results also show that with LIMS microprobe data, it is possible to identify chemical differences between individual microfossils, thereby providing new insights about nature of early life. Analysis of LIMS spectra acquired from the individual microfossils reveals complex mineralization, which can reflect the metabolic diversity of the Gunflint microbiome. An intensity-based machine learning model trained on LIMS Gunflint data might be applied for the future investigations of putative microfossils from silicified matrices, where morphological integrity of investigated structures is lost, and potentially in the investigation of rocks acquired from the Martian surface.

Polycyclic aromatic hydrocarbons (PAHs) are thought to play an important role as indicators for chemical processes in the interiors and on the surfaces of planets and moons. Based on the strength of the Unidentified Infrared Bands it is estimated that 10 –25% of all carbon in the ISM joins together to form the multi-ringed structure of PAHs [Tielens, 2008]. Therefore, this class of molecules is a ubiquitous and important tracer of chemical processes, which can be investigated with instruments on space exploration missions. The ORganics Information Gathering INstrument (ORIGIN) is a prototype space instrument developed and built at the University of Bern, Switzerland, for the detection of biomolecules on planetary surfaces [Ligterink et al., 2020] [Riedo et al., 2013]. ORIGIN is Laser Ionization Mass Spectrometer (LIMS) operated at desorption conditions. A single 266 nm nanosecond laser pulse is used to desorb and ionize gently molecules from a steel sample surface, located in a vacuum chamber at a pressure of P-7 mbar. The ions are subsequently detected with a miniature reflectron-type time-of-flight mass analyser. The steel sample holder is placed onto an xyz-translation stage, which allows accurate positioning relative to the mass analyser and to analyse samples at multiple positions. Four different PAHs were investigated in this measurement campaign: Anthracene (C14H10), Coronene (C24H12), Pyrene (C16H10), and Perylene (C20H12), which are representative of PAHs of different structures and sizes. These molecules are analysed at different average surface concentrations (0.1 – 700 picomol mm-2) and laser pulse energies (1-4 µJ). Figure 1 shows the mass spectra of the four PAHs measured at 4 µJ, demonstrating for the first time ORIGINs' ability to detect these species. The instrument shows the highest sensitivity for Coronene and the lowest for Anthracene. Identifying peaks for Coronene, Perylene and Pyrene can be detected even at a pulse energy of 1 µJ. At a higher laser pulse energy of 3 µJ, surface concentrations as low as 0.14 picomol mm-2 could be detected in the case of Pyrene, indicating that the limit of detection is even lower. Fragmentation of the PAHs is simple and limited, which reduces isobaric interferences of these molecules in complex mixtures and makes their identification easier. Moreover, the observed PAH fragments do not overlap with signatures from amino acids investigated earlier [Ligterink et al., 2020], meaning that if both species are present a reliable identification is possible. Note that at elevated mass/charge ratios of beyond 400 broadened mass peaks are observed. The ion optical setup used for this campaign was optimised for peaks below a mass of 300 and will be improved for upcoming studies. The result of this measurement campaign shows that ORIGIN can detect PAHs at low surface concentrations and different laser pulse energies. This further shows the capabilities of the instrument in analysing the composition of planetary surfaces, the results of which can be used to characterize the chemical environments. References: Tielens, A.G.G.M. Interstellar polycyclic aromatic hydrocarbon molecules. Annual Review of Astronomy and Astrophysics, 46(1):289–337, 2008 Ligterink, N.F.W., Grimaudo, V., Moreno-García, P. et al. ORIGIN: a novel and compact Laser Desorption – Mass Spectrometry system for sensitive in situ detection of amino acids on extraterrestrial surfaces. Sci Rep 10, 9641 (2020). Riedo, A. Bieler, M. Neuland, M. Tulej, and P. Wurz, Performance evaluation of a miniature laser ablation time-of-flight mass spectrometer designed for in situ investigations in planetary space research, J. Mass Spectrom., 48, 2013, 1 - 15

Accurate isotope ratio measurements are of high importance in various scientific fields, ranging from radio isotope geochronology of solids to studies of element isotopes fractionated by living organisms. Instrument limitations, such as unresolved isobaric inferences in the mass spectra, or cosampling of the material of interest together with the matrix material may reduce the quality of isotope measurements. Here, we describe a method for accurate isotope ratio measurements using our laser ablation ionization time-of-flight mass spectrometer (LIMS) that is designed for in situ planetary research. The method is based on chemical depth profiling that allows for identifying micrometer scale inclusions embedded in surrounding rocks with different composition inside the bulk of the sample. The data used for precise isotope measurements are improved using a spectrum cleaning procedure that ensures removal of low quality spectra. Furthermore, correlation of isotopes of an element is used to identify and reject the data points that, for example, do not belong to the species of interest. The measurements were conducted using IR femtosecond laser irradiation focused on the sample surface to a spot size of ~12 μm. Material removal was conducted for a predefined number of laser shots, and time-of-flight mass spectra were recorded for each of the ablated layers. Measurements were conducted on NIST SRM 986 Ni isotope standard, trevorite mineral, and micrometer-sized inclusions embedded in aragonite. Our measurements demonstrate that element isotope ratios can be measured with accuracies and precision at the permille level, exemplified by the analysis of B, Mg, and Ni element isotopes. The method applied will be used for in situ investigation of samples on planetary surfaces, for accurate quantification of element fractionation induced by, for example, past or present life or by geochemical processes.

Mass spectrometric measurements conducted on various amino acids that are relevant to life as we know it on Earth are presented using ORIGIN. ORIGIN is a novel Laser Desorption Mass Spectrometric setup designed for in situ operation on planetary surfaces, including the icy surfaces on ocean worlds such as Europa and Enceladus. Laser desorption measurements were conducted on single amino acids and amino acid mixtures to investigate their fragmentation behaviour at given laser settings. Simple mixtures consisting of four amino acids and a complex mixture consisting of ten amino acids at various concentrations and with components ranging from Glycine to Tyrosine are investigated. The unique fragmentation patterns observed for the single amino acids allowed successfully the identification of amino acids in the complex mixture. The measurement capabilities of ORIGIN are of high importance as ORIGIN represents an alternative instrument to traditional space instruments for future space exploration missions devoted to the detection of life. Introduction The icy moons Europa and Enceladus of Jupiter and Saturn, respectively, represent promising objects in our Solar System that may host life in their liquid oceans underneath their ice crust. Through cracks in the ice shells signatures of life, such as amino acids, lipids, among others, may escape the liquid oceans and form deposits on the surface, which can be probed more easily by instrumentation than in the ocean directly. However, in situ operation of instrumentation designed for the detection of signatures of life is extremely challenging and sensitive instrumentation is required to withstand the harsh environmental conditions that exist at the ice surfaces. In our contribution, we present the current figures of merit of our newly developed laser desorption mass spectrometric instrument, called ORIGIN. Experimental Sample Preparation. Solutions of single amino acids (ranging from Gly to Tyr) at a concentration of 100 µM, mixtures of four amino acids (Ala, Asp, Met, and Tyr, at total concentrations of 100µM), and a mixture of ten amino acids (Gly, Ala, B-Ala, Ser, Asp, Leu, Glu, Met, His, Tyr) of a total mixture concentration of 100 µM (singles have a concentration down to 2.5 µM), were prepared and drop cast (1 µl) under atmospheric condition and at room temperature into shallow cavities (0.2 mm x Ø 3 mm) on sample holders [1]. LDMS Measurements. Measurements were conducted using our newly developed laser desorption mass spectrometric setup, called ORIGIN [1]. ORIGIN consists of a miniature reflectron-type time-of-flight mass analyser (160 mm x Ø 60 mm) [2,3] that is coupled to a nanosecond pulsed laser system (pulse width ~3 ns, wavelength λ = 266 nm, pulse repetition rate = 20 Hz). The mass analyser is located within a vacuum chamber that is evacuated to a base pressure down to the mid 10-8 mbar level. An optical beam delivery system guides the laser pulses from the nanosecond laser system towards the vacuum chamber, towards the lens system that is just installed outside, above the entrance window of the vacuum chamber. The laser pulses are focussed through the mass analyser towards the sample surface to induce the desorption of the analyte of interest. The sample holder that consists of cavities is placed outside the laser focus to gently desorbed the analyte (laser spot size at the level of ~30 µm). With each laser pulse, sample material is desorbed and partially ionised. Only positively charged species can enter the entrance ion optics of the mass analyser, and are subsequently guided to the detector system. The charged species arrive in time sequences at the detector system, and a quadratic equation is used for the conversion of the time-of-flight spectra to mass spectra. In this study, we discuss measurements conducted on single amino acids, four simple mixtures of amino acids at different concentrations, and on a mixture that consists of ten amino acids at different concentrations down to 2.5 µM level. The biofilms were sampled spot-wise by applying 100 laser shots per position. In total 40 positions were sampled on each biofilm (single amino acid, simple and more complex mixtures). Results and Discussion From the measurements of single amino acids their fragmentation behaviour can be determined accurately. Subsequently, these fragmentation patterns allowed for the direct identification of amino acids in the more simple mixtures and the more complex mixture by fitting the mass spectra of the mixtures. Moreover, it is possible to simulate the entire laser desorption mass spectrometric of the mixtures. In Figure 1 the laser desorption measurements conducted on one of the simple mixtures are shown (top panel) whereas at the bottom panel the simulated spectrum is shown. As can be observed, both spectra are almost identical to each other, which is of high importance as the simulation allows reliable identification of amino acids within a mixture. Figure 1: Measured (top) and simulated (bottom) laser desorption mass spectra of a simple amino acid mixture that consists of Ala, Met, Asp, and Tyr. Summary and Conclusions Laser desorption mass spectrometric studies were conducted on single amino acids to investigate their simple and robust fragmentation pattern and on simple and more complex mixtures of amino acids. Through simple fragmentation patterns observed for single amino acid measurements, amino acids in simpler and more complex mixtures could be identified directly. Moreover, the robust fragmentation patterns observed allowed to simulate mass spectra of amino acid mixtures. The latter is of high importance as it allows reliable post-measurement identification of amino acids. The study presented is of high importance for future space exploration missions because ORIGIN represents a promising analytical tool for the identification of signatures of life, if present, on e.g., the icy surface of Europa. References [1] Ligterink, N.F.W., Grimaudo, V., Moreno-García, P., Lukmanov, R., Tulej, M., Leya, I., Lindner, R., Wurz, P., Cockell, C.S., Ehrenfreund, P., and Riedo, A., Nature Sci. Rep., Vol. 10, 2020, 9641. [2] Riedo, A., Bieler, A., Neuland, M., Tulej M., and Wurz, P., J. Mass Spectrom., Vol. 48, 1 - 15, 2013. [3] Riedo, A., Meyer, S., Heredia, B., Neuland, M., Bieler, A., Tulej, M., Leya, I., Iakovleva, M., Mezger K., and Wurz P., Planet. Space Sci., Vol. 87, 1 - 13, 2013.

In-situ Mars exploration requires new promising instrumentation that will be capable of delivering highly accurate chemical information about soils and rocks present at the Martian surface. Specific attention is drawn to the instruments that are capable of identifying extinct or extant microbes within the bulk of various solid samples (Tulej et al., 2015; Westall et al., 2015; Wiesendanger et al., 2018). A miniature Laser Ablation/Ionization Mass Spectrometer (LIMS) developed at the University of Bern is among the valid candidates (Wurz et al., 2012). The size of the mass analyzer is only Ø 60 mm × 160 mm and thus capable of being deployed on a rover or lander platform. In this contribution, we will present data collected from a 1.88 Ga Gunflint sample using a deep UV fs laser system as ablation ion source. The gunflint chert sample contains a population of microfossils entombed in the silica matrix and was chosen as a Martian analogue. Using the high stability of the UV laser and consequent uniform ablation, we performed large-scale spectra collection (90’000) in two modes - chemical imaging and depth profiling. With the current setup, we achieved a diameter of the analytical spot of ~10 µm for the depth profiling and ~5 µm for the imaging. Our results reveal that our LIMS instrument can identify the location of the microfossil lamination area as well as single microfossils by chemical means. We show how single mass unit spectral decomposition and subsequent kernel clustering reveal masses and intensity regions unique to the microfossils and inorganic host, thus providing the opportunity for automated identification of the spectra that are collected from the microfossils. We also show how transforming spectral intensities into spectral proximities can help to navigate the rich multidimensional datasets. We also address common interpretation problems in LIMS, when multiple mineralogical inclusions contribute to the output spectra acquired within the single analytical spot using ρ-networks and Principal Component Analysis (PCA). In combination with analysis of spectral proximities, this approach is particularly useful in attempts to assess the biogenicity of the putative terrestrial microfossils as well as potential Martian microfossils. Additionally, we discuss the data analysis pipeline and chemical composition of the microfossils and surrounding inorganic host in detail. Tulej M., Neubeck A., Ivarsson M., Riedo A., Neuland M. B., Meyer S., and Wurz P. (2015) Chemical Composition of Micrometer-Sized Filaments in an Aragonite Host by a Miniature Laser Ablation/Ionization Mass Spectrometer. Astrobiology, 15: 669-682. Westall F., Foucher F., Bost N., Bertrand M., Loizeau D., Vago J. L., Kminek G., Gaboyer F., Campbell K. A., Bréhéret J.-G. and others. (2015) Biosignatures on Mars: What, Where, and How? Implications for the Search for Martian Life. Astrobiology, 15: 998-1029. Wiesendanger R., Wacey D., Tulej M., Neubeck A., Ivarsson M., Grimaudo V., Moreno-García P., Cedeño-López A., Riedo A., Wurz P. and others. (2018) Chemical and Optical Identification of Micrometer-Sized 1.9 Billion-Year-Old Fossils by Combining a Miniature Laser Ablation Ionization Mass Spectrometry System with an Optical Microscope. Astrobiology, 18: 1071-1080. Wurz P., Abplanalp D., Tulej M., Iakovleva M., Fernandes V. A., Chumikov A., and Managadze G. G. (2012) Mass spectrometric analysis in planetary science: Investigation of the surface and the atmosphere. Solar System Research, 46: 408-422.

Searches for the past and present life on the planetary surfaces will be involving multilevel characterisation of the planetary rocks and soils within potentially habitable environments. Some up to three billion years old stromatolites or fossilised bacterial colonies are particularly interesting. They are found on the Earth and thought to be earliest life forms preserved within the terrestrial sedimentary rocks and can be a benchmark for searches of bio-relevant objects on planetary surfaces. By combining the microscope-camera system and mass analyser one can identify micro-fossilised material within the rocks by means of specific morphological details and characteristic chemical composition. We discuss the results of the studies on ancient microfossils obtained by space-born instrumentation, microscope-camera system combined with laser mass spectrometer. Both, the microscope imaging and chemical analyses can be conducted with micrometre spatial resolution. We demonstrate that the morphological record is helpful but not sufficient to identify bio-relevant material. Yet, while combined with elemental and isotope and with help depth profiling method, the compositional analysis can distinguish between abiotic and biological nature of the material. Detection of biosignature in measurements of fossilised materials with a miniature laser ablation ionisation mass analyser. [1] M. Tulej, A. Neubeck, M. Ivarsson, A. Riedo, M.B. Neuland, S. Meyer, P. Wurz, Chemical Composition of Micrometer-Sized Filaments in an Aragonite Host by a Miniature Laser Ablation/Ionization Mass Spectrometer, Astrobiology, 15 (2015) 669-682. [2] A. Neubeck, M. Tulej, M. Ivarsson, C. Broman, A. Riedo, S. McMahon, P. Wurz, S. Bengtson, Mineralogical determination in situ of a highly heterogeneous material using a miniaturized laser ablation mass spectrometer with high spatial resolution, International Journal of Astrobiology, 15 (2016) 133-146. [3] R. Wiesendanger, D. Wacey, M. Tulej, A. Neubeck, M. Ivarsson, V. Grimaudo, P. Moreno-Garcia, A. Cedeno-Lopez, A. Riedo, P. Wurz, Chemical and optical identification of micrometer-sized 1.9 billion-year-old fossils by combining a miniature laser ablation ionization mass spectrometry system with an optical microscope, Astrobiology, 18 (2018) 1071-1080. [4] A. Riedo, A. Bieler, M. Neuland, M. Tulej, P. Wurz, Performance evaluation of a miniature laser ablation time-of-flight mass spectrometer designed for in situ investigations in planetary space research, Journal of Mass Spectrometry, 48 (2013) 1-15. [5] M. Tulej, A. Riedo, M.B. Neuland, S. Meyer, P. Wurz, N. Thomas, V. Grimaudo, P. Moreno-Garcia, P. Broekmann, A. Neubeck, M. Ivarsson, CAMAM: A Miniature Laser Ablation Ionisation Mass Spectrometer and Microscope-Camera System for In Situ Investigation of the Composition and Morphology of Extraterrestrial Materials, Geostand Geoanal Res, 38 (2014) 441-466.

For the last four decades space exploration missions have searched for molecular life on planetary surfaces beyond Earth. Often pyrolysis gas chromatography mass spectrometry has been used as payload on such space exploration missions. These instruments have relatively low detection sensitivity and their measurements are often undermined by the presence of chloride salts and minerals. Currently, ocean worlds in the outer Solar System, such as the icy moons Europa and Enceladus, represent potentially habitable environments and are therefore prime targets for the search for biosignatures. For future space exploration missions, novel measurement concepts, capable of detecting low concentrations of biomolecules with significantly improved sensitivity and specificity are required. Here we report on a novel analytical technique for the detection of extremely low concentrations of amino acids using ORIGIN, a compact and lightweight laser desorption ionization – mass spectrometer designed and developed for in situ space exploration missions. The identified unique mass fragmentation patterns of amino acids coupled to a multi-position laser scan, allows for a robust identification and quantification of amino acids. With a detection limit of a few fmol mm−2, and the possibility for sub-fmol detection sensitivity, this measurement technique excels current space exploration systems by three orders of magnitude. Moreover, our detection method is not affected by chemical alterations through surface minerals and/or salts, such as NaCl that is expected to be present at the percent level on ocean worlds. Our results demonstrate that ORIGIN is a promising instrument for the detection of signatures of life and ready for upcoming space missions, such as the Europa Lander.

In this contribution we present the design and first measurement results obtained with a new high-performance laser ablation and ionisation (LIMS) mass spectrometer for solid sample analysis named “LMS-GT”, combining high mass- and high spatial resolving powers. The instrument consists of a fs-laser ablation ion source coupled to a time-of-flight (TOF) mass spectrometer that provides measurements with a mass resolution (m/Δm) of 10 000 at full width half max and more over a wide mass range. This resolution enables the separation of the most important isobaric interferences between clusters, molecules and multiple charged ions. Thereby it enables significant improvements of the quantitative analysis of complex samples with the LIMS-TOF technique. The instrument performance is demonstrated by analysis of measurements conducted on various NIST standard reference materials (SRMs). Using these samples we determined detection limits in the ppm range and below, and relative sensitivity coefficients (RSCs), in the range between 0.1 and 10.

The identification of microbial remains on planetary bodies is an extremely challenging endeavor, requiring the utilization of novel measurement techniques and modern analytical approaches. We performed an extensive study of the chert sample from Gunflint formation (1.88 Ga) containing populations of Precambrian microfossils with a laser ablation ionization mass spectrometer (LIMS) (Riedo et al., 2013; Wiesendanger et al., 2018) intended for application in space. Chemical characterization on microscale can open a new perspective in the identification of microbial remains, where morphological features might be lost and provide additional lines of evidence towards proving biogenicity of a given putative sample. Chert from the Gunflint formation in this study is considered as a Martian analogue where remains of microfossils are mainly concentrated within circular and tubular structures, which are primarily made from collapsed cell walls entombed within silica.We sampled the microfossils and surrounding chert (host area) with fs UV laser with a spot size of 8 μm and retrieved intensities of 180 consecutive single mass peaks from each mass spectrum. We collected 60’000 mass spectra and build an intensity-based classifier, intended to process large datasets from cherts and identify their classes in an automatic regime. Using elemental pair-to-pair correlation analysis, we identified relevant masses for each given mineralogical class. Additionally, we will present results of chemical imaging of the sample and discuss in details the chemical composition of microfossils and surrounding chert as well as technical aspects of the identification of spectra from the microfossils.We will show how rich spectral information can be reduced to the low dimensional domain using principal components analysis and used for successful classification. Moreover, we will present the established workflow and discuss possibilities to extend this approach to other astrobiologically relevant formations, such as phosphates, carbonates, hydrothermal silicates. Future Mars exploration with enabling technologies as machine learning and big data processing coupled with high-output instrumentation such as laser ablation ionization time-of-flight mass spectrometry has the capacity to improve scientific return and achieve stated objectives and therefore should be given appropriate attention in the future missions. Riedo, A., Neuland, M., Meyer, S., Tulej, M., & Wurz, P. (2013). Coupling of LMS with a fs-laser ablation ion source: Elemental and isotope composition measurements. Journal of Analytical Atomic Spectrometry, 28(8), 1256–1269.Wiesendanger, R., Wacey, D., Tulej, M., Neubeck, A., Ivarsson, M., Grimaudo, V., … Wurz, P. (2018). Chemical and Optical Identification of Micrometer-Sized 1.9 Billion-Year-Old Fossils by Combining a Miniature Laser Ablation Ionization Mass Spectrometry System with an Optical Microscope. Astrobiology, 18(8), 1071–1080.

Stable nickel isotopes are known to fractionate by biological processes and their measurements can be important biomarker. In searches for ancient fossilised materials such as microbial cells, the Ni isotope fractionation record can be preserved after death and fossilization of microstructures. Typically, transition metal isotopes in microfossils are difficult to measure accurately because of their low concentration in the fossil. Furthermore, microsized fossil structures are difficult to isolate from the host phase. Thus, the measurement of their chemical composition can be conducted only by a few analytical methods. We have applied femtosecond-laser ablation/ionisation time-of-flight mass spectrometry (LIMS) to measure chemical composition of the fossilised material embedded in the aragonite phase and accurately derive the Ni isotopic fractionation pattern. High resolution depth profiling method was applied to isolate fossilised material composition from the host phase. The mass peak intensity correlation and peak integration methods were subsequently applied to derive isotope concentrations. The accuracies and precision in permill level or better of the isotope values were achieved. For comparison the studies of Ni isotopes were conducted on inorganic samples. The instrument used in the studies is a miniature mass analyser developed for space research holding promisses that differentiation between abiotic and biogenic microstructures in rocks can be studied also in situ on the surfaces of Solar System bodies.References1. U. Rohner et al., Meas. Sci. Technol. 14 (2003) 2159–21642. A. Riedo et al., JAAS, 28:1256–1269, 20133. A. Neubeck et al., Int. J. Astrobiology, 15, 133-146, 20164. M. Tulej et al., Astrobiology, 2015, DOI: 10.1089/ast.2015.1304;JAAS,33(8):1292-1303, 20185. S. Meyer et al., J. Mass Spectrom. 2017, DOI: org/10.1002/jms.3964 6. R. Wisendanger et al., J. Chemometrics, 2018, DOI: 10.1002/cem.30817. V. Grimaudo et al., Anal. Chem., 2018, DOI: 10.1021/acs.analchem.7b05313

Rationale: Laser ablation combined with mass spectrometry forms a promising tool for chemical depth profiling of solids. At irradiations near the ablation threshold, high depth resolutions are achieved. However, at these conditions, a large fraction of ablated species is neutral and therefore invisible to the instrument. To compensate for this effect, an additional ionization step can be introduced. Methods: Double-pulse laser ablation is frequently used in material sciences to produce shallow craters. We apply double-pulse UV femtosecond (fs) Laser Ablation Ionization Mass Spectrometry to investigate the depth profiling performance. The first pulse energy is set to gentle ablation conditions, whereas the second pulse is applied at a delay and a pulse energy promoting the highest possible ion yield. Results: The experiments were performed on a Cr/Ni multi-layered standard. For a mean ablation rate of ~3 nm/pulse (~72 nJ/pulse), a delay of ~73 ps provided optimal results. By further increasing the energy of the second pulse (5–30% higher with respect to the first pulse) an enhancement of up to 15 times the single pulse intensity was achieved. These conditions resulted in mean depth resolutions of ~37 and ~30 nm for the Cr and Ni layers, respectively. Conclusions: It is demonstrated on the thin-film standard that the double-pulse excitation scheme substantially enhances the chemical depth profiling resolution of LIMS with respect to the single-pulse scheme. The post-ionization allows for extraordinarily low ablation rates and for quantitative and stoichiometric analysis of nm-thick films/coatings.

The identification of extraterrestrial life is one the most exciting and challenging endeavors in space research. The existence of extinct or extant life can be inferred from biogenic elements, isotopes, and molecules, but accurate and sensitive instruments are needed. In this whitepaper we show that Laser-based Mass Spectrometers are promising instrument for the in situ identification of atomic, isotopic, and molecular biosignatures. An overview of Laser ablation/Ionization Mass Spectrometry (LIMS) and Laser Desorption/Ionization Mass Spectrometry (LD-MS) instruments developed for space exploration is given. Their uses are discussed in the context of a Mars scenario and a Europa scenario. We show that Laser-based Mass Spectrometers are versatile and technologically mature instruments with many beneficial characteristics for the detection of life. Future planetary lander and rover missions should be encouraged to make use of Laser-based Mass Spectrometry instruments in their scientific payload., Comment: 10 pages, 1 figure. Submitted as a whitepaper for the Planetary Science and Astrobiology Decadal Survey 2023-2032

The application of a novel UV fs Laser Ablation Ionization Mass Spectrometry approach for chemical depth profiling of low-melting point, high surface roughness SnAg solder bump features is presented. The obtained submicrometer resolved three-dimensional compositional data reveal unprecedented information on the distribution of individual elements inside the solder bump matrix. Moreover, the determination of matrix-matched relative sensitivity coefficients allows the first report on quantitative assessment of the SnAg alloy composition. These results significantly contribute to an in-depth understanding of the SnAg plating process. This experimental procedure may find application in future additive performance screening.

Laser ablation ionization mass spectrometry studies on polished surface structures of hard, high melting point multicomponent interconnect structures using our femtosecond-laser time-of-flight mass spectrometer have previously been proven capable of providing spatially resolved chemical depth profile data at the micro- and nanometer level. Transfer of experimental protocols tailored to suit such type of samples to low melting point materials with high surface roughness, however, is highly challenging, as thermal effects caused by interactions of the laser light with the targeted surface play a severe role in the latter case and may significantly deteriorate the analysis outcome. In this contribution we present a dedicated and detailed comparison of the distinct effects of near infrared and ultraviolet irradiation on the ablation process in femtosecond laser ablation ionization mass spectrometry studies on low melting point materials. As model substrate we use high surface roughness, as- deposited SnAg solder alloy, a material of major industrial relevance in microchip fabrication. We will demonstrate herein that polydimethylsiloxane replica casting is possible also from granularly structured, high surface roughness samples. Characterization of the laser ablation craters as well as of their polydimethylsiloxane replicas is carried out by mass spectrometric analysis, Scanning Electron Microscopy imaging, and furthermore, as a novel approach for this purpose, by white light interferometry. Integration of all obtained results signifi-cantly adds to the detailed understanding of laser ablation processes on low melting point, high surface roughness materials and allows identifying optimal depth profiling conditions for these demanding samples.

Accumulation of spectra is a common approach for improvement of the signalto‐ noise ratio (SNR) in mass spectrometry. However, severe degradation of the overall spectrum can occur if some individual mass spectra, affected by peak broadening, are included in the accumulation process. In this contribution, we discuss potential sources and effects of spectral distortions by using examples from mass spectra acquired by our miniature laser ablation/ionisation time‐of‐flight mass spectrometer. We show how recent developments in acquisition systems enable to identify individual spectra subjected to peak broadening and present a filtering method capable of systematic and reproducible exclusion of such spectra from the accumulation process. We show that the method can be used on a wide range of materials and present a detailed case study performed on a trevorite mineral sample. Using this method, improvements of the isotope accuracy of Si, Ni, and Cr by factors between 1.6 and 7.7 were achieved. Finally, we discuss the limitations of the method and provide complementary analysis of other materials in the supplementary documents provided with this contribution. KEYWORDS