Edward R. Birnbaum PhD
Edward R. Birnbaum PhD
Professor Emeritus of Chemistry
BS (Brooklyn College)
MS (University of Illinois)
PhD (University of Illinois)
Calcium-Binding Peptides and Proteins
Using lanthanide spectroscopy to probe a wide variety of systems. Applying phosphazene chemistry as the basis for new classes of dendrimers and combining them with more conventional polymeric species to produce novel compounds
The incomplete 4f subshells of the lanthanide ions Ce3+ to Yb3+ result in a variety of magnetic and spectroscopic properties that are of interest from both a theoretical and practical perspective. For example, gadolinium (Gd3+) coordination complexes are administered to patients in order to enhance images obtained using MRI (Magnetic Resonance Imaging) instruments. Similarly, the fluorescence behavior of the lanthanide ions, especially Eu3+ and Tb3+, are used to generate the images on a color TV screen. The fluorescence properties in particular make these ions excellent probes of systems in which they are either already present or into which they can be incorporated. The fluorescence is easily observed, has a relatively long lifetime (~0.1 to 10 msec), and exhibits very sharp lines. In the case of the europium ion, each unique chemical species present in solution or in the solid state results in a single peak in the fluorescence excitation spectrum. For example, when the two calcium ions that are normally present in the muscle protein parvalbumin are replaced by Eu3+ ions, two fluorescence peaks are observed in the excitation spectrum, one for each calcium ion binding site. The wavelength at which the fluorescence peaks appear in the excitation spectrum, the lifetime of the fluorescence signal, and the number of peaks present in the emission spectrum all contain information that can be used to characterize the protein environment. We are interested in using the unique fluorescence properties of these ions to probe a wide variety of systems, including calcium-binding proteins that play a role in many important biological processes and inorganic materials such as the YBa2Cu3O7-x high temperature superconductors and their analogs for which it is possible to replace the yttrium ion (Y3+) with the Eu3+ ion.
The phosphazene class of compounds contains the P=N functional group and can be found in both cyclic arrangements and linear polymers. This class of compounds, whose cyclic trimer, P3N3Cl6 superficially mimics benzene, can be prepared with a large variety of species replacing the chlorine atoms. We are interested in using these compounds as the basis for new classes of dendrimers and combining them with more conventional polymeric species to produce novel compounds that have unusual chemical properties.
Selected Scholarly Activity
“Many-Body Nonradiative Energy Transfer in a Crystalline Europium(III) EDTA Complex,” H-Y. D. Ke and E. R. Birnbaum, J. Luminescence, 1995,63, 9–17.
“Characterization of the Carboxy Groups on Datura innoxia Using Eu(III)Luminescence,” H-Y. D. Ke, E. R. Birnbaum, D. W. Darnall, and G. D.Rayson, Environ. Sci. Technol., 1992, 26, 782–788.
“Eu3+ Luminescence Studies of Oncomodulin. The Origin of the pH-Dependent Behavior,” C. L. Trevino, W. A. Palmisano, E. R. Birnbaum,and M. T. Henzl, J. Biological Chem., 1990, 265, 9694.
|Mailing address:||University of Sciences|
600 South 43rd Street
Philadelphia, PA 19104-4495
e [dot] birnba [at] usciences [dot] edu