Publications by authors named "R H Heeren"

Drug toxicity during the development of candidate pharmaceuticals is the leading cause of discontinuation in preclinical drug discovery and development. Traditionally, the cause of the toxicity is often determined by histological examination, clinical pathology, and the detection of drugs and/or metabolites by liquid chromatography-mass spectrometry (LC-MS). While these techniques individually provide information on the pathological effects of the drug and the detection of metabolites, they cannot provide specific molecular spatial information without additional experiments.

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Biobased poly(ethylene furanoate) (PEF)/poly(ε-caprolactone) (PCL) block copolymers have been synthesized using ring opening polymerization (ROP) of ε-caprolactone (ε-CL) in the presence of PEF in different mass ratios. An increase in intrinsic viscosity is observed for the block copolymers with higher ε-CL content due to the extension of their macromolecular chain. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MS) was employed to understand the composition and structure of the produced block copolymers.

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In the field of cultural heritage, and more specifically in oil paintings, the ability to unambiguously identify and locate metal soaps is of great interest for a better understanding of painting degradation. Here, we demonstrate the use of a Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) instrument capable of tandem mass spectrometry imaging for the unambiguous identification and localization of lead soaps in cross sections of samples of old oil paintings at high spatial resolution. It is shown that the specific fragmentation pattern of lead soaps is dictated by the loss of the lead ion and that fragmentation occurs on the hydrocarbon chains of the fatty acids.

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In the dynamic field of drug discovery and development, a comprehensive understanding of drug absorption, distribution, metabolism, excretion, and toxicity is crucial. Mass spectrometry imaging (MSI) has become a key analytical tool in the pharmaceutical industry, allowing evaluation of drug biodistribution and molecular profiles. Antisense oligonucleotides (ASOs) are emerging drug candidates for treating neurologic diseases.

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Mass spectrometry imaging (MSI) techniques enable the generation of molecular maps from complex and heterogeneous matrices. A burger patty, whether plant-based or meat-based, represents one such complex matrix where studying the spatial distribution of components can unveil crucial features relevant to the consumer experience or production process. Furthermore, the MSI data can aid in the classification of ingredients and composition.

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