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Knowledge on the temporal and size distribution of particulate matter (PM) in air as well as on its elemental composition is a key information for source appointment, for the investigation of their influence on environmental processes and for providing reliable data for climate models. While cascade impactors allow for time- and size-resolved collection of airborne PM, total reflection X-ray fluorescence (TXRF) allows for element-sensitive investigation of minute sample amounts thanks to its detection sensitivity. But during quantification by means of TXRF it is crucial to be aware of the linear calibration limits of TXRF in order to identify situations where collection times or pollution levels in the different size partitions were exceedingly long or high. Indeed, TXRF can only be reliably used when the amount of matter collected on the top of the substrate is sufficiently small. By means of grazing incidence X-ray fluorescence (GIXRF), where the excitation conditions are varied in a controlled and reliable manner and include also the TXRF regime, a self consistent quantification of elemental mass depositions can be performed in order to validate or falsify TXRF quantification results. For low mass depositions an agreement within a few percent for the different excitation conditions was found, while for increasing amounts of material relative errors of up to a factor of 4 were found for TXRF as compared to GIXRF. Thus, TXRF cannot be applied to all samples regardless of their coverage and threshold values for the validity of quantification results need to be determined. As a flexible solution, GIXRF allows extending the dynamic range of reliably quantifiable mass depositions beyond the linear regime of TXRF, an important advantage when variable amounts of airborne PM need to be quantified as in the case of collection with cascade impactors. The presented more reliable quantification approach can be transferred to mobile tabletop instrumentation as well. This aspect is highly relevant for air quality monitoring in terms of supporting the introduction of appropriate legislation and measures for health and climate protection as well as for supporting their enforcement., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Herein we report on the hydrolysis mechanism of [Pt{N(p-HC 6 F 4 )CH 2 } 2 (NC 5 H 5 ) 2 (OH) 2 ], a platinum(IV) complex that exhibits anti-cancer properties. Atomic telemetry, an in situ technique based on electron structure sensitive X-ray spectroscopy, revealed that hydrolysis preceded any reduction of the metal center. The obtained results are complemented with 19 F NMR measurements and theoretical calculations and support the observation that this Pt IV complex does not reduce spontaneously to Pt II in HEPES buffer solution at pH 7.4 and after 24 h incubation. These results are of importance for the design of novel Pt-based coordination complexes as well as understanding their behavior under physiological conditions., (Copyright © 2018 Elsevier Inc. All rights reserved.)

This review presents a new application of Resonant X-ray Emission Spectroscopy (RXES) to study the mechanism of action of metal containing anticancer derivatives and in particular platinum in situ and in vivo. The technique is an example of a photon-in photon-out X-ray spectroscopic approach, which enables chemical speciation of drugs to be determined and therefore to derive action mechanisms, and to determine drug binding rates under physiological conditions and therapeutic concentrations. This is made feasible due to the atomic specificity and high penetration depth of RXES. The review presents examples of the three main types of information that can be obtained by RXES and establishes an experimental protocol to perfect the measurements within cells., (Copyright © 2015 Elsevier Ltd. All rights reserved.)