The ESA mission Rosetta, launched on March 2nd, 2004, carries an instrument suite to the comet 67P/Churyumov-Gerasimenko. The COmetary Secondary Ion Mass Anaylzer -COSIMA -is one of three cometary dust analyzing instruments onboard Rosetta. COSIMA is based on the analytic measurement method of secondary ion mass spectrometry (SIMS). The experiment's goal is in-situ analysis of the elemental composition (and isotopic composition of key elements) of cometary grains. The chemical characterization will include the main organic components, present homologous and functional groups, as well as the mineralogical and petrographical classification of the inorganic phases. All this analysis is closely related to the chemistry and history of the early solar system. COSIMA covers a mass range from 1 to 3500 amu with a mass resolution m/ m @ 50% of 2000 at mass 100 amu. Cometary dust is collected on special, metal covered, targets, which are handled by a target manipulation unit. Once exposed to the cometary dust environment, the collected dust grains are located on the target by a microscopic camera. A pulsed primary indium ion beam (among other entities) releases secondary ions from the dust grains. These ions, either positive or negative, are selected and accelerated by electrical fields and travel a well-defined distance through a drift tube and an ion reflector. A microsphere plate with dedicated amplifier is used to detect the ions. The arrival times of the ions are digitized, and the mass spectra of the secondary ions are calculated from these time-of-flight spectra. Through the instrument commissioning, COSIMA took the very first SIMS spectra of the targets in space. COSIMA will be the first instrument applying the SIMS technique in-situ to cometary grain analysis as Rosetta approaches the comet 67P/Churyumov-Gerasimenko, after a long journey of 10 years, in 2014.

A set of mass spectral classifiers has been developed to recognize presence or absence of 70 substructures or more general structural properties in a molecule. Classification is based on numerical transformation of low resolution mass spectral data, automatic selection of appropriate features, multivariate discriminant methods, and estimation of the reliability of the classification answer. Examples demonstrate applications in structure elucidation together with automatic isomer generation as well as combination with results obtained by the CHEMICS system.

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The plant growth regulator chlormequat, an involatile quaternary ammonium salt, has been quantified by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOFMS). Restrictions for quantitative MALDI-TOFMS analysis, such as irreproducible crystallisation and unsatisfactory laser stability, have been overcome by the application of two synthesised isotopically labelled standards and the optimisation of the measurement protocol. Data acquisition at constant laser power was compared to data acquisition at approximately constant ion abundance of the relevant ions (analyte and internal standards). Data acquisition at constant ion abundance performed better and enabled a high number of consecutive firings to the same sample deposition area. Furthermore an increased sample-to-sample repeatability and a high reproducibility over several weeks without re-calibration have been attained by this method. Linearity over three orders of magnitude (0.05 to 30 ng/microL chlormequat), with a correlation coefficient of 0.9997, was achieved using [13C3]-chlormequat as internal standard. Limit of detection and limit of determination were determined to be in the low pg/microL range for pure standard solutions. Thin-layer chromatography was applied for the removal of high amounts of choline, which is often present in plant tissue extracts and can adversely affect the ionisation and detection of chlormequat by MALDI-TOFMS. The use of two internal standards ([13C3]- and [2H9]-chlormequat) enabled direct quantification and simultaneous control of the recovery.

Six QCM resonators forming a sensor array were coated with different molecularly imprinted polymers for the on-line monitoring of composting procedures. Four key analytes are traced, namely water, 1-propanol, ethyl acetate and limonene. Trendlines obtained on-line by the sensor during measurements in a commercial composter give a distinct pattern: the signal for the alcohols first decreases according to an increase in ethyl acetate concentration, and increases again, when obviously no more acetic acid is formed. Limonene is detected in later stages of composting. Similar trends could also be observed by GC-MS. Additionally, chromatographic and sensor data for limonene could be correlated with each other.