University of Massachusetts Lowell

Department of Chemistry

Ryan Research Group

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Fluorescence and NMR of Humic Materials

A major focus of my research continues to be the use of fluorescence spectroscopy to investigate the interactions of pollutants with natural organic materials (i.e., humic materials). Fluorescence quenching and enhancement phenomena are being studied as the means to assess binding reactions of metal ions (Cu2+, Al3+, Ni2+) and synthetic organic compounds (amines) with fulvic and humic acid. An important part of this research is the development of data treatments or models that can adequately describe the relationship between the fluorescence intensity change and the binding of these complex materials.

Recently we have begun to explore the use of Nuclear Magnetic Resonance (NMR) spectroscopy for metal binding studies. Several NMR techniques are being investigated, including: relaxation times (T1), solvent suppression, solid-state NMR, and 27Al NMR to assess metal complexation by humic materials.


Bioaccumulation of Metals
  We have been measuring the bioaccumulation of metals by the marine mussel, Mytilus edulis, in both laboratory and field studies in collaboration with Dr. William E. Robinson, a biologist at UMass Boston. Laboratory studies have dealt with physiological questions such as the sites of metal uptake and elimination in the organism and transport of metals between organs and through the blood. Field work has concentrated on the use of mussels as indicator organisms for monitoring coastal waters and the prediction of seawater metal levels from the measurement of bioaccumulation by mussel transplants.


Environmental Analysis
  Accurate measurements of pollutants in the environment are a critical first step in efforts to clean up contaminated sites. Our laboratory has been involved in the analysis of soils, sediments, water and biota from around Massachusetts, Mexico and Central America. The main thrust of the work has been the analysis of metals by plasma emission, ICP-MS and Instrumental Neutron Activation Analysis (INAA). Current studies are focusing on sediment and water quality in the Lowell canals.  Recently, we have also started, in collaboration with DEP, to investigate storm-drain waters.


Analysis of alpha-Tocopherol (Vitamin E)
  The analysis of alpha-tocopherol (vitamin E) has been undertaken to determine the best sources for this commercially important product. This study is in collaboration with Dr. Eugene Rogers of UMass Lowell's Department of Clinical Laboratory Sciences.


Ocean Sequestration of CO2
  Carbon Dioxide droplets are stabilized by particles and emulsions are formed.  These innovative emulsions have several advantages for carbon dioxide sequestration in geologic formations or the deep oceans, but also can be used for enhanced oil recovery and other valuable applications.  This research is a collaboration with Dr. Dan Golomb of UMass Lowell's Department of Atmospheric Sciences.  Please consult Environ. Sci. Technol., 38(16), 4445-4450, 2004, Ind. Eng. Chem. Res., 45, 2728-2733, 2006 or Environ. Sci. Technol., 41(12), 4698-4704, 2007,  for details.



If you are interested in any of these projects, please contact us.  [contact info]