Lynn Francesconi

The Francesconi Lab investigates the chemistry of technetium (Tc) and the lanthanides. As Tc-99m, technetium is the most widely used isotope in the nuclear medicine clinic for diagnosis of disease. The Francesconi Lab, in collaboration with Diatide and Schering, has identified the structures of two recent targeted Tc-99m radiopharmaceuticals, AcuTect™ and NeoTect™ that are now in the clinic for imaging Deep Vein Thrombosis (DVT) and lung tumors, respectively. The lab is transitioning to radiotherapy applications employing rhenium-188 (Re-188), the third row congener of Tc, as well as radiolanthanides.

The isotope Tc-99 is a major fission product of uranium-235 and is found in radioactive waste tanks from the production of plutonium in the 1940-1950s.  The redox activity of Tc hampers the separation of Tc-99 from spent fuel rods and radioactive tank waste and also presents a problem in the identification of a suitable wasteform for Tc-99.   To address these important needs of the country, the Francesconi Lab is investigating the speciation, chemistry and stability of Tc-99 incorporated into metal oxide matrices. The lab is also employing polyoxometalates that are nanometer sized transition metal oxide aggregates, to reduce pertechnetate (Tc(VII)), the Tc species extracted from spent fuel rods,  to lower valent states and to stabilize the low valent Tc species.

The lab also works on a project to study speciation of lanthanides that are incorporated into polyoxometalates.  Lanthanide ions are important in applications as luminescent probes, catalysts and as radioactive isotopes, for therapy of diseases.  Understanding the speciation of lanthanides “anchored” in  polyoxometalates is important for development of improved luminescent materials and catalysts as well as new separations agents for radiolanthanides.

• 31P Magic Angle Spinning NMR Spectroscopy of Paramagnetic Rare-Earth-Substituted Keggin and Wells-Dawson Solids . Huang, W.; Schopfer, M.; Zhang, C.; Howell, R. C.; Todaro, L.; Gee, B. A.; Francesconi, L. C.; Polenova, T. J. Am. Chem. Soc.; (Article); 2008; 130(2); 481-490.
• Cantorias, M.V.; Howell, R.C. Todaro, L.; Cyr, J.E.; Berndorff, D.;Rogers, R.D.; Francesconi, L.C. “MO Tripeptide Diastereomers (M=99/99mTc,Re): Models to Identify the Structure of 99mTc Peptide Targeted Radiopharmaceuticals”  Inorg. Chem., 2007, 46 (18), 7326-7340.
• Cyr, J.E.; Pearson, D.A.; Nelson, C.A.; Lyons, B.A.; Zheng, Y.; Bartis, J.; He, J.; Cantorias, M.V.; Howell, R.C.; Francesconi, L.C. “Isolation, Charcterization, and Biological Evaluation of Syn and Anti Diastereomers of Tc-99m Depreotide:  A Somatostatin Receptor Binding Tumor Imaging Agent” J. Med. Chem. (Article), 2007, 50 (18) 4295-4303.
• Huang, W.; Francesconi, L.C.; Polenova, T. “31P Magic Angle Spinning NMR Spectroscopy for Probing Local Environments in Paramagnetic Europium-Substituted Wells-Dawson Polyoxotungstates", Inorg.  Chem., 2007, 46 (19), 7861-7869.
• Boglio, C.; Lenoble, G.; Duhayon, C.; Hasenknopf, B.; Thouvenot, R.; Zhang, C.; Howell, R.C.; Burton-Pye, B.P.; Francesconi, L.C.; Lacote, E.; Thorimbert, S.; Malacria, M.; Afonso, C.; Tabet, J.-C. “Production and Reactions of Organic-Soluble Lanthanide Complexes of the Monolacunary Dawson [a1-P2W17O61]10- Polyoxotungstate” Inorg. Chem., 2006, 45(3); 1389-1398.