Research Interests

1. Real Time Studies of Contaminant Transformations in Natural Environments

Work in the AERL, has led to the ongoing development of an innovative and powerful analytical technique known as membrane introduction mass spectrometry (MIMS). The technique uses a semi-permeable PDMS membrane as a direct sample introduction platform to a quadrupole ion trap mass spectrometer. Because no sample preparation is required, this approach provides rapid quantification directly in the complex sample mixtures. The technique is very sensitive for volatile and semi-volatile organic compounds and can be used to study contaminant processes in ‘real-time’ at environmentally relevant concentrations and matrices.

MIMS has been demonstrated in our lab to be a useful tool to investigate the fate and distribution of volatile and semi-volatile organic pollutants at low ppb concentrations in situ. For instance, studies in our labs have followed the formation of dis-infection by-products in drinking water and the photo-degradation of organic pollutants in natural waters. This work will help us better understand the role of naturally occurring dissolved organic matter and the factors that influence the photochemistry of xenobiotics in natural waters.

2.  Development and Application of Membrane Based Analytical Methods

Developing 'faster, better, cheaper' analytical methods is important in it's own right as rapid detection has immediate application in environmental monitoring, emergency response and medical diagnosis. Furthermore, the novel application of these techniques provides a unique opportunity to investigate physico-chemical properties of both permeants and new materials.  We have recently constructed several new membrane based sample introduction platforms which extend the range and versatility of membrane inlet mass spectrometry. These flow through systems provide time-resolved analytical data, which allows for convenient study of dynamic processes. In addition to studying the kinetics of chemical reactions, we have recently applied our system to investigate membrane transport phenomena. By analyzing the dynamics of the non-steady state signal increase in response to a step function increase in analyte concentration, we are able to extract mass transport parameters such as has diffusion and partition coefficients.

3. Air & Water Quality - Land Use Interactions

Over the past decades, there has been a growing appreciation environmental protection and an increased awareness of the importance of a ‘source to tap’ approach to drinking water protection. Many of the threats to water quality in coastal BC are important on a global scale and include such activities as agriculture, forestry, mining, oil and gas exploration and urbanization. We are working with several stakeholders and government agencies to get a better understanding of land-water interactions. The AERL has state-of-the-art instrumentation to measure nutrient ions as well as dissolved organic carbon and nitrogen. We are working to develop predictive tools that will help guide future development and provide environmental protection. In the laboratory, we are working towards developing novel analytical tools, such as membrane introduction mass spectrometry as a rapid screening tool for biomarkers of both air and water quality.

One of the goals of our research will be to identify key land-use water quality interactions that are important in coastal watersheds. These studies will lead to improved land use practices and better protection of drinking water and aquatic ecosystems.

NSERC DISCOVERY GROUP GRANT TITLE - Membrane Introduction Mass Spectrometry

Positions Available

We are looking for qualified undergraduates students to work on directed research projects either as summer employment or CHEM 490. Our group is currently seeking graduate students to work in collaboration with the Applied Environmental Research Laboratories. For further information please contact us directly (Erik. Krogh@viu.ca).