ChromICP
The goal of ChromICP is to completely replace the "organic ICPMS mode" practiced for more than 30 years with innovative, yet simple and easily accessible chromatographic approaches that do not compromise detection sensitivity for hydrophobic compounds, thereby opening up new areas in speciation analysis. We are building on successes demonstrated in our recent pioneering work in this emerging field of research, with examples such as the concept of "ion repulsion chromatography", the introduction of novel organic solvents with exceptional elution strength and plasma compatibility (e.g. hexanediol) and a new generation of ion-pair reagents (fluoroalkylamines) which, unlike polymer-based ion-exchange chromatography columns, offer mild and controllable retention and are highly compatible with techniques based on electrospray ionization and molecular mass spectrometry.
The introduction of tandem mass spectrometry in ICPMS enables the extension of this technique to non-metals. We perform multi-element speciation analyses, including non-metals such as sulphur, phosphorus and chlorine in natural matrices derived from fungi and plant species, with the aim of identifying new compounds with biological and medicinal activity and improving our understanding of the metabolic diversity of related elements.
Research in this area lead to the identification of naturally occurring dichloroacetic acid in the edible mushroom Russula nigricans which may influence our view of the occurrence of the halogenated acetic acids in nature
Organic solvents are required to elute hydrophobic compounds in liquid chromatography, which is a major challenge for chromatographic detection with ICPMS due to the very poor tolerance of carbon by plasma. This limits the sensitivity and accessibility for applications with highly hydrophobic compounds. We introduce novel chromatographic elution approaches and new chromatographic eluents with the aim to change the common practice in chromatographic ICPMS coupling to achieve unprecedented detection limits while simplifying the experimental setup.
A milestone in this area of research is the introduction of 1,2 hexanediol as a novel chromatographic eluent in HPLC-ICPMS, which enabled previously unachievable instrumental limits of detection for hydrophobic compounds such as the arsenic-containing fatty acids
Hydrogen sulphide is the newest member of the group of gaseous signaling molecules, but is difficult to measure directly in body fluids. Novel and selective biomarkers that reflect its concentrations in human tissue under normal and pathophysiological conditions are needed to demonstrate the clinical relevance of the hydrogen sulfide signaling pathway. We identify new metabolites in humans that can serve as selective and sensitive biomarkers for the endogenous production of this signaling molecule and investigate their applicability under clinical conditions.
In the course of this research, trimethylsulfonium was identified in human urine as a stable and non-volatile methylation metabolite of hydrogen sulfide.