William T. Cooper

Research

ENVIRONMENTAL GEOCHEMISTRY OF NATURAL WATERS AND SEDIMENTS

Research in our group is focused on the organic geochemistry of natural waters and watersheds. This includes studies of the biogeochemical reactivity of naturally occurring organic compounds (i.e. “humic substances”), as well as the development of more powerful spectral identification methods for the complex mixtures commonly found in nature. Water bodies are dynamic, and the ecological impacts and ultimate fate of anthropogenic chemical contaminants introduced into them are largely dependent on their reactions with the "natural" constituents of the watershed. Unfortunately, the underlying chemical principles governing these reactions are largely unknown, primarily because of a lack of sufficiently powerful analytical techniques. Our goal is a detailed understanding of the environmental geochemistry of surface and ground waters, with a major emphasis on development and application of new analytical techniques.

MASS SPECTROMETRY AND NMR SPECTROSCOPY

We are working with scientists at the National High Magnetic Field Laboratory on the development and application of advanced mass spectrometry techniques for characterizing humic substances in a variety of surface waters. Using the ultra–high-resolution capabilities of high field (9.4 and 14 T) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), we have determined the molecular formulas of thousands of individual humic molecules with mass accuracies previously unobtainable. We are now focusing on molecular structures of humic substances containing nitrogen and phosphorus in order to better understand N and P cycling in wetlands, estuaries and coastal zones.

Figure 1. Ultrahigh resolution mass spectrum of dissolved organic nitrogen (DON) in a treatment wetland. Here we have highlighted a 0.30 Dalton window at nominal mass 432 of the spectrum and identified peaks that contain one or three N atoms.

Figure 2. Microbial transformations of DON. Formulas of DON compounds identified by FT-ICR MS are reduced to elemental ratios (O/C and H/C) and projected onto a van Krevelen diagram. T0 Specific Formulas (purple) were uniquely present in a surface water sample before 5 days of microbial incubation; T3 Specific Formulas (gold) were uniquely present after the incubation.

Our mass spectrometry efforts are supported by additional spectroscopic measurements. For example, we use direct- and cross-polarization solid state ¹³C NMR to characterize solid soil phases in peatlands that have released dissolved organic matter (DOM) into porewaters. Individual molecular species in the released DOM are identified by FT-ICR MS, while forms of organic phosphorous are identified by solution ³¹P NMR.

INTEGRATED ANALYTICAL & GEOCHEMICAL RESEARCH

We have a number of projects that integrate these advanced analytical methods into field research in climate change, marine chemistry, soil science and wastewater engineering. These include: qualitative and quantitative characterization of organic forms of important aquatic nutrients (C, N, P) in coastal sediments by high-field FT- ICR MS; measurements of the chemical dynamics of carbon sequestration in northern peatlands by FT-ICR MS, ¹³C NMR and three dimensional excitation emission matrix (EEMS) fluorescence spectroscopy; characterization of the chemical composition and spin-dynamics of soil biochar organic matter (i.e. "black carbon") by ¹³C and ¹⁵P NMR; and characterization of organic matter in water and wastewater after advanced oxidation by ozonation and UV irradiation. We work with scientists and engineers from all over the world and currently have active projects with collaborators in New Zealand, Germany, Panama and Brazil.

Students

GRADUATE STUDENTS

Dan Osborne
Project: Identifying Molecular Changes to Effluent Dissolved Organic Matter in Landfill Leachates after Advanced Oxidation

Rasha Hamden
Project: Effect of Biomass Type and Pyrolysis Conditions on the Rearrangement of Carbon and Phosphorus Forms in Biochar as Determined by Solid-State 13C-NMR and Liquid-State 31P-NMR Spectroscopy

David Podgorski
Project: Molecular Composition of Wastewaters Optimized for Growth of Algae Bioenergy Feedstocks

Malak Tfaily
Project: Molecular Characterization of Dissolved Organic Matter (DOM) in Northern Peatlands: Understanding the Chemical Dynamics of Climate Change

Allison Paul
Project: A Comprehensive Assessment of the Transformation of Dissolved Organic Matter in Natural Water and Wastewater Systems During Ozone Treatment and Ultra Violet Radiation

Aopeau Imvittaya
Project: Ion Chromatography Separation with Mass Spectral Identification of Ionositol Phosphates in Soils

UNDERGRADUATES

Chris Witowski
Project: Lipid Profiles of Algae Grown for Biofuel Feedstocks

Recent Publications

1. Tfaily, M.M., Hamdan, R., Corbett, J.E., Chanton, J.P., Glaser, P.H., Cooper, W.T. Investigating Dissolved Organic Matter Decomposition in Northern Peatlands using Complimentary Analytical Techniques, Geochim. Cosmochim. Acta, 112, 116-129, 2013. DOI 10.1016/j.gca.2013.03.002.

2. Osborne, D.M., Podgorski, D.C., Bronk, D.A., Roberts, Q., Sipler, R.E., Austin, D., Bays, J.S., Cooper, W.T. Molecular-Level Characterization of Reactive and Refractory Dissolved Organic Nitrogen Compounds in a Nutrient-Impacted River, Rap. Comm. Mass Spectrom., 27, 1-8, 2013.

3. Corbett, E.J., Tfaily, M.M., Burdige, D.J., Cooper, W.T., Glaser, P.H., Chanton, J.P. "Partitioning pathways of CO2 production in peatlands with stable carbon isotopes", Global Biogeochem. Cycles, DOI 10.1007/s10533-012-9813-1, 2012.

4. Lin, X., Green, S. Tfaily, M.M., Prakash, O.M., Konstantinidis, K., Corbett, E.J., Chanton, J.P., Cooper, W.T., Kostka, J.E. "Structure and function of microbial communities from multiple domains covaries with geochemical gradients linked to plant species composition in the Glacial Lake Agassiz Peatland of northern Minnesota", Appl. Environ. Microbiol.. 78, 7023-7031, 2012.

5. Jaffé, R., Yamashita, Y., Maie, N., Cooper, W.T., Dittmar, T., Dodds, W., Jones, J., Myoshi, T., Ortiz-Zayas, J.R., Podgorski, D., Watanabe, A. "Dissolved Organic Matter in Headwater Streams: Compositional Variability across Climatic Regions", Geochim. Cosmochim. Acta, DOI 10.1016/j.gca.2012.06.031, 94, 95-108, 2012.

6. Tfaily, M.M., Hodgkins, S., Podgorski, D.C., Chanton, J.P., Cooper, W.T. "Comparison of Dialysis and Solid-phase Extraction for Isolation and Concentration of Dissolved Organic Matter Prior to Fourier Transform Ion Cyclotron Resonance Mass Spectrometry", Anal. Bioanal. Chem., 404, 447-457, 2012.

7. Podgorski, D.C., McKenna, A.M., Rodgers, R.P., Marshall, A.G., Cooper, W.T. "Selective ionization of dissolved organic nitrogen by positive ion atmospheric pressure photoionization coupled with Fourier transform ion cyclotron resonance mass spectrometry, Anal. Chem., 84, 5085-5090, 2012.

8. Hamdan, R., El-Rifai, H.M., Cheesman, A.W., Turner, B.L., Reddy, K.R., Cooper, W.T. "Linking Phosphorus Sequestration to Carbon Humification in Wetland Soils by 31P and 13C NMR Spectroscopy", Environ. Sci. Technol. 46, 4775-4782, 2012.

9. Podgorski, D.C., Hamdan, R., McKenna, A.M., Nyadong, L., Rodgers, R.P., Marshall, A.G., Cooper, W.T. Characterization of Pyrogenic Black Carbon by Desorption Atmospheric Pressure Photoionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry", Anal. Chem., 84, 1281-1287. 2012.

10. Tfaily, M.M., Podgorski, D.C., Corbett, J.E., Cooper, W.T. "Influence of acidification on the optical properties and molecular composition of dissolved organic matter", Analytica Chimica Acta, 706. 261- 267, 2011.

11. D'Andrilli, J., Dittmar, T., Koch, B.P., Purcell, J.M., Marshall, A.G., Cooper, W.T. "Comprehensive Characterization of Marine Dissolved Organic Matter by FT-ICR Mass Spectrometry with Electrospray and Atmospheric Pressure Photoionization", Rap. Comm. Mass Spectrom. 24. 643-650, 2010.

12. D'Andrilli, J. Chanton, J.P., Glaser, P.H., Cooper, W.T. "Characterization of Dissolved Organic Matter in Northern Peatland Soil Porewaters Using Ultrahigh Resolution Mass Spectrometry", Org. Geochem., 41, 791-799. 2010.

13. Gonsior, M., Peake, B.M., Cooper, W.T., Podgorski, D., D'Andrilli, J., Dittmar, T., Cooper, W.J. "Characterization of dissolved organic matter across the Subtropical Convergence off the South Island, New Zealand", Mar. Chem., 123, 99-110. 2010.

Grants

National Science Foundation: Collaborative Research: Black Carbon Remineralization in the Environment: Physical and Chemical Controls, 2008-2011. EAR-0819811

National Science Foundation: Quantifying Dissolved Organic Matter Degradation in Filtering Shelf Sands, 2007-2010 (co-PI with M. Huettel and J. Kostka, FSU Oceanography). OCE-0726754

National Science Foundation: Collaborative Research: An Interdisciplinary Investigation of Groundwater-Carbon Coupling in Large Peat Basins and its Relation to Climate Change, 2006-2010 (co-PI with J. Chanton, FSU Oceanography). EAR-0628349

National Science Foundation, U.S.-Brazil Program: The Role of Intertidal Environments in Global Biogeochemical Cycles: Planning visit for the Establishment of a Brazilian-US Research and Education Initiative, 2008-2010. OISE-0710744

The Institute for Energy Systems, Economics, and Sustainability (ISES) of Florida State University: Center for Marine Bioenergy Research (co-PI with J. Kostka and others, Florida State University).

South Florida Water Management District (through CH2M Hill): Identification of Reactive and Refractory Dissolved Organic Nitrogen Compounds in a Water Quality Treatment Project near the Caloosahatchee River, 2009.

Courses

Introduction to Analytical Chemistry: CHM 3120