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Pulmonary arterial hypertension (PAH) is a rare and deadly disease affecting roughly 15–60 people per million in Europe with a poorly understood pathology. There are currently no diagnostic tools for early detection nor does a curative treatment exist. The lipid composition of arteries in lung tissue samples from human PAH and control patients were investigated using matrix-assisted laser desorption ionization (MALDI) imaging mass spectrometry (IMS) combined with time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging. Using random forests as an IMS data analysis technique, it was possible to identify the ion at m/z 885.6 as a marker of PAH in human lung tissue. The m/z 885.6 ion intensity was shown to be significantly higher around diseased arteries and was confirmed to be a diacylglycerophosphoinositol PI­(C18:0/C20:4) via MS/MS using a novel hybrid SIMS instrument. The discovery of a potential biomarker opens up new research avenues which may finally lead to a better understanding of the PAH pathology and highlights the vital role IMS can play in modern biomedical research.

A sputter beam, consisting of large O clusters, was used to record depth profiles of alkali metal ions (Me) within thin SiO layers. The O gas cluster ion beam (O-GCIB) exhibits an erosion rate comparable to the frequently used O projectiles. However, because of its high sputter yield the necessary beam current is considerably lower (factor 50), resulting in a decreased amount of excess charges at the SiO surface. Hence, a reduced electric field is obtained within the remaining dielectric layer. This drastically mitigates the Me migration artifact, commonly observed in depth profiles of various dielectric materials, if analyzed by time-of-flight secondary ion mass spectrometry (ToF-SIMS) in dual beam mode. It is shown, that the application of O-GCIB results in a negligible residual ion migration for Na and K. This enables artifact-free depth profiling with high sensitivity and low operational effort. Furthermore, insight into the migration behavior of Me during O sputtering is given by switching the sputter beam from O to O clusters and vice versa. K is found to be transported through the SiO layer only within the proceeding sputter front. For Na a steadily increasing fraction is observed, which migrates through the unaffected SiO layer toward the adjacent Si/SiO interface.

We have carried out a basic study on the charge transfer across the interface between LiNi 0.5 Mn 1.5 O 4 (LNMO) thin-film cathodes and different solid electrolyte coatings, namely LiNbO 3 , ZrO 2 and Li 4 Ti 5 O 12 . In contact to LNMO, the spinel material Li 4 Ti 5 O 12 should act as a solid electrolyte, since it exhibits a very low electronic conductivity in the fully oxidized state. The thin films were prepared by means of sol-gel chemistry and spin-coating. The electrochemical and interfacial properties were studied by combining electrochemical impedance spectroscopy (EIS), time-of-flight secondary-ion mass spectrometry (ToF-SIMS) and cross-sectional SEM imaging. The results show that the LNMO / LiNbO 3 interface combines a low charge transfer resistance with a high stability.