University of Southern Maine

Synthesis and characterization of group 14 metalloles Professors Tracy, Ford, and Prudenté; Professors Mullin (UNE) and Benferamo (St. Joseph's)

This project is focused on the synthesis of new group 14 metalloles, metalla-fluorenes, and their derivatives, the photophysical characterization of the new compounds, and the development of chemical sensors, immunoassay schemes, and electroluminescent devices constructed using the most promising of these new compounds. Efforts are directed toward the synthesis of derivatives with varying solubilities, enhanced native luminescence, and targeted emission wavelength characteristics.

Publications

• Jerome L. Mullin, Henry J. Tracy, James R. Ford, Scott R. Keenan and Fred Fridman, "Characteristics of Aggregation Induced Emission in 1,1-dimethyl,2,3,4,5-tetraphenyl- and hexaphenyl Siloles and Germoles", Journal of Inorganic and Organometallic Polymers and Materials, 2007, 17, 201-213.
• Henry J. Tracy, Jerome L. Mullin, Wim T. Klooster, James A. Martin, Judith Haug, Scott Wallace, Issac Rudloe, and Kimberly Watts, “Enhanced Photoluminescence from Group 14 Metalloles in Aggregated and Solid Solutions,” Inorg. Chem. 2005, 44, 2003-2011.

Presentations

• Fecteau, K., Tracy, H., Bozeman, T., Benfaremo, N, Ford, J., Mullin, J., "Novel naphthyl substituted siloles: Synthesis, characterization, and photoluminescent properties", presentation at 235^th ACS National Meeting, April 2008.
• Henry J. Tracy, Trevor Bozeman, James Ford, Nicholas Benfaremo, Jerome L. Mullin and Danielle L. Woodall, "Novel silole derivatives: Synthesis, characterization, and photoluminescence properties", at the 234^th ACS National Meeting, Boston, MA., Aug 2007.
• Jerome L. Mullin, Henry J. Tracy, James R. Ford, Scott R. Keenan and Fred Fridman, "Exploring the Mechanism of Aggregation-induced Emission (AIE) in Group 14 Metalloles", at the 232^nd ACS National Meeting, San Francisco, CA., Sept 2006.

Energy transfer in lanthanide/mixed d10 metal dicyanides Professors Tracy and Ford; Professors Mullin (UNE) and Patterson (UM)

Many lanthanides exhibit strong fluorescence in the visible spectrum, with narrow emission bands characteristic of atomic energy level transitions. Lanthanide mixed-metal dicyanides, prepared by precipitation from aqueous solutions of trivalent lanthanide ions and varying amounts of aqueous gold and silver dicyanides, display both sharp atomic emissions and a high energy, broader emission attributed to the metal dicyanide. Furthermore, analysis of the excitation spectra of these compounds reveals striking evidence of a tunable energy transfer from the metal dicyanides to the lanthanide ion. The efficiency of this transfer process can be changed by varying the ratio of gold to silver.

Publications

• Haiyan Lu, James Ford, Henry J. Tracy, Alora B. Carrier, Aaron Keller, Jerome L. Mullin, Michelle J. Poissan, Samuel Sawan and Howard H. Patterson, "Tunable Energy Transfer from d¹⁰ Metal-Metal Bonded Dicyanide(I) Donor Ions to Terbium(III) Acceptor Ions in Luminescent Tb[Ag_xAu_1-x(CN₂)]₃ (x=0-1)", Chem. Phys. Lett., 2007, 443, 55-60.

Presentations

• Ford, J., Tracy, H., Carrier, A., Mullin, J., "Energy transfer in dry grind mixtures of terbium-mixed metal dicyanides", presentation at 235^th ACS National Meeting, April 2008 (presenter).
• Libby, J., Toye, S., Walls, H., Ford, J., "Chemistry Laboratory Research Curriculum: Synthesis and Photophysical Characterization of Lanthanide-mixed d¹⁰ metal dicyanide compounds", at the Seventh Annual USM Thinking Matters Symposium, Portland, ME., April 2008. [poster]
• Henry J. Tracy, James Ford, Jerome L. Mullin, Alora Johnson and Aaron Keller, "Resonance energy transfer and tunable photoluminescence of terbium(III) heterobimetallic dicyanoaurate(I)-dicyanoargentate(I) powders", at the 232^nd ACS National Meeting, San Francisco, CA., Sept 2006.

Synthesizing substituted pyrolidines from β-amino radical precursors Professor Prudenté

USM Professor Prudenté exploits the reactivity of aziridines and aziridinium ions to generate substituted pyrolidines and beta-amino acid derivatives. The pyrolidine and beta-amino acid structural units are found in naturally occurring and synthetic compounds that display antibiotic, antifungal, cytotoxic functions, as well as enzyme inhibition and DNA binding capability. This project, originally supported by the American Chemical Society’s Petroleum Research Fund, is an integral part of the organic laboratory curriculum. Starting with different substrates, students explore various synthetic methodologies aimed at generating substituted aziridines.

Presentations

• Gail Willette and Caryn Prudenté, "Radical Aziridinum Ions," presented at the 231^st ACS National meeting, April 2006
• Laura Fraley and Caryn Prudenté, "Beta-amino Radicals Generated from Single-Electron Reduction of Aziridinium Ions," presented at the 231^st ACS National meeting, April 2006

Designing antibody-based diagnostic tools to detect environmental mercury Professor Prudenté

This project focuses on preparing synthetically modified proteins, carbohydrates, peptides, and other biopolymers to afford compounds that demonstrate interesting immunological characteristics. The modified substrates are used to design antibody-based diagnostic tools capable of testing environmental samples for mercury contamination.

Publications

• Caryn K. Prudenté and Margaret C. Hausman. "Organomercury Bioconjugate Synthesis and Characterization by Matrix Assisted Laser Desorption Ionization Mass Spectrometry," Bioconjugate Chem. 2003, 14, 1270 -79.
• Elizabeth A. Stemmler, Anthony B. Costa, Caryn K. Prudenté and Margaret C. Hausman. "The Characterization of an Organomercury Hapten and Bioconjugate using Matrix Assisted Laser Desorption Ionization Mass Spectrometry." Proceedings of the 52^nd ASMS Conference on Mass Spectrometry and Allied Topics, May 23 - 27, 2004. [abstract]

Presentations

• Sean Cote and Caryn Prudenté, "Development of immunochemical methods to detect mercury," presented at the 235^th ACS National meeting, April 2008 [poster]
• Rebekah Pilling and Caryn K. Prudenté, "Development and Screening of an Anti-Mercury Diagnostic Using Novel Organomercury Bioconjugates," presented at the 231^st ACS National meeting, April 2006 [poster]
• Elizabeth A. Stemmler, Anthony B. Costal, Caryn K. Prudenté, and Margaret C. Hausman, "Characterization of an Organomercury Hapten and Bioconjugate using MALDI-FTMS," at the 52^nd American Society of Mass Spectrometry Meeting, Nashville TN, May 2004.

Levels and fate of environmental contaminants Professor Benedict

Professor Benedict is investigating various contaminants (PAHs, PCBs, Dioxins/Furans, and heavy metals) in samples ranging from river sediments to cigarette wastes. For our cigarette study we are investigating levels of environmental contaminants that leach out from improperly disposed of cigarette wastes. Another project that is ongoing is the study of emerging and historical environmental contaminants in sediment cores from local river basins.

Nutrient cycling in the Presumpscot River Basin Professor Benedict

Professor Benedict's research group is studying nutrient cycling, and the impacts of agricultural and urban nutrient loading on local tributaries.