Gayle E. Woloschak, Ph.D.

Departments of Radiation Oncology, Radiology, and Cell and Molecular Biology

Northwestern University, Argonne National Laboratory

TiO2 oligonucleotide nanocomposites are 45° nanoparticles of titanium dioxide semiconductor combined with oligonucleotide DNA(s).  The titanium nanoparticle in the nanocomposites is photoreactive and the oligonucleotide has base-pairing specificity.  Exposure to electromagnetic radiation of energies greater than 3.2 eV results in charge separation, leading to irreversible trapping of protons and cleavage of DNA associated with the nanocomposite.  In addition to DNA, we have been able to attach to the surface fluorescent and MR contrast agents thus permitting multifunctional use of the nanoparticles.  In addition, we have been able to modify some of the core shell materials to provide additional properties for the nanocomposites.  Finally, we have introduced the nanocomposites into mammalian cells, and they have retained sequence-specific hybridization capabilities; nanocomposites with DNA specific for rDNA are retained in nucleoli and those with DNA specific for mitochondria are retained in mitochondria of cells.

Dr. Gayle Woloschak is a Professor in the Departments of Radiation Oncology, Radiology, and Cell and Molecular Biology at Northwestern University.