Detection and imaging of selected organic chemicals on soil interfaces in the millimeter- to micrometer-range by micro GC/LC- and DESI mass spectrometry

Principle investigator: Prof. Dr. Dr. h.c. Michael Spiteller

Co-worker: Dr. Sebastian Zühlke

Hypotheses
• The strength of the binding and the degree of transformation of organic chemicals is a result of the intrinsic chemical properties of the compounds studied and the surface biology and chemistry of the soils investigated. Therefore, changes of the surface properties due to changes in redox potential or supply of organic manure should directly influence the sorption and degradation kinetic of the model compounds.

• Ageing of geochemical surfaces results in a change of the chemical and biological status. This phenomenon alters the sorption and biodegradation of chemicals, which is often erroneously described with "constants".

Goals
Analytical experiments with high spatial and temporal resolution at the mm to µm range with new methods in mass spectrometry will be conducted. Six chemicals covering a wide variety of physical and chemical properties will be selected and their binding and fate should be studied by GC-MS and LC-MS. In addition, desorption electrospray ionization mass spectrometry (DESI-MS), a recently introduced technique for the analysis of surfaces at ambient conditions, will be applied for the first time to shed light on the role of the various parameters influencing the binding and fate of the chemicals on geochemical surfaces. We intend to work on the same scale and with similar samples as groups who are focusing on biological effects (Smalla, BBA) in order to link the results of both approaches. This will answer the question whether biological "hot spots" are responsible for a faster decline and metabolism of chemicals on certain domains of the soil surface. Samples will be taken either from own experiments or those from batch experiments (Kögel-Knabner, TU Munich) or soil column experiments (Totsche, Jena and Kästner, UFZ Leipzig).


Cooperations
TU Munich, Prof. Kögel-Knabner concerning the preparation of artificial soils
Providing analytical methods to BBA Braunschweig, Dr. Smalla, UFZ Leipzig, Prof. Kästner and FSU Jena, Prof. Totsche for the multi component analysis of the selected chemicals based on mass spectrometry
Input parameters for sorption and kinetic for mathematical modelling to BOKU Vienna, Prof. Gerzabek



DESI ion source 

DESI-ion source (Prosolia Inc. Indianapolis, USA)

Poster Spiteller 

Publications

Ding, G.-C., Heuer, H., Zühlke, S., Spiteller, M., Pronk, G.J., Heister, K., Kögel-Knabner, I., Smalla, K. 2010. Soil type-dependent responses to phenanthrene as revealed by determining the diversity and abundance of polycyclic aromatic hydrocarbon ring-hydroxylating dioxygenase genes by using a novel PCR detection system. Appl. Environ. Microbiol. 76, 4765-4771.

Zhang, H., Spiteller, M., Guenther, K., Boehmler, G., Zühlke, S. 2009. Degradation of a chiral nonylphenol isomer in two agricultural soils. Environ. Pollut. 157, 1904-1910.