ChromICP
The inductively coupled plasma mass spectrometry (ICPMS) is an element-selective technique that can be coupled with separation technologies and employed for speciation analysis with wide applications in targeted and non-targeted analysis. The advent of triple quadrupole technology to the technique (ICPMS/MS) greatly improved the detection capability for non-metal elements which we have demonstrated in recent years by some of the earliest applications of the technique for hydrophilic compounds tagged with non-metal elements such as chlorine (e.g. haloacetic acids), phosphorous (e.g. phosphorous containing herbicides), and sulfur (e.g. taurine). However, ICPMS poorly tolerates organic solvents and this has been a major gap between ICPMS and liquid chromatography that has been addressed over the previous decades using the “organic ICPMS mode” which involves instrumental set-up and experimental conditions that can greatly decrease sensitivity for hydrophobic compounds, rendering many areas in non-metal speciation analysis, where ICPMS/MS detection can show great potential, poorly accessible. A striking and demonstrative example in the literature relates to arsenic speciation, where LOD for hydrophilic As species (e.g. DMA) can be as low as 0.001 µg L-1 and for highly hydrophobic As compounds such as arsenolipids can exceed 1 µg L-1. This gap indicates that unlocking the full potential of the technique awaits major chromatographic developments.
The ambitious aim of ChromICP is to entirely replace the “organic ICPMS mode” practiced over more than 30 years with innovative yet simple and easily accessible chromatographic approaches that do not compromise detection sensitivity for hydrophobic compounds and thereby unlock new areas in speciation analysis. We build on success shown 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 tolerability (e.g., hexanediol), and a new generation of ion-pairing reagents (fluoroalkylamines) which provide mild and controllable retention, unlike polymer-based ion-exchange chromatographic columns, and show high compatibility with techniques based on electrospray ionization and molecular mass spectrometry.
Furthermore, in addition to collaborating with research groups inside and outside the local department who are interested in our chromatographic approaches, we aim to take advantage of the introduced developments and demonstrate their applicability by exploring under-investigated areas that can be made more accessible in the field of non-metal speciation analysis using the new approaches. We are interested in the non-metals chlorine, bromine, phosphorous, and sulfur. Relevant applications of interest include (1) studying the occurrence, mobility, biotransformation, and bioaccumulation of heritage and emerging hydrophobic halogenated environmental contaminants, (2) investigating the environmental and biological occurrence and functions of halolipids, and (3) the identification of novel natural products tagged with a non-metal.
Current projects:
- Trimethylsulfonium production in humans (FWF P 32379 stand-alone project)
- Gradient elution in LC-ICPMS with standard conditions
- Investigating Sulfonylureas with ion-repulsion chromatography
- Novel organic solvents as mobile phases in LC-ICPMS
- Identification of natural organohalogens of medicinal value
More information on our “Research Projects” page.