Fatima Rizvi1,2, Tamara Koritarov1,3, Nada Dimitrijevic1, Vani Konda3, Marc Bissonnette3, Tijana Rajh1
1Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois
2Department of Bioengineering, University of Illinois, Chicago, Illinois
3Department of Medicine, The University of Chicago, Chicago Illinois
Nanotechnology offers efficient solutions for many areas of science and technology spanning from solar cells to medicine. Owing to rapid development of synthesis and nanofabrication methods we are able to engineer advanced materials at atomic and molecular levels and assemble them into functional devices. Integration of inorganic nanoparticles with soft and biological materials results in one of promising types of hybrids for advancing medical technologies. TiO2 nanoparticles with their extraordinary stability, exceptional photoreactivity and biocompatibility have a special place in biomedical solutions of the future. Reconstructed surfaces of TiO2 nanoparticles differ from the bulk by the presence of highly reactive under-coordinated surface. The coordination sphere of the surface metal atoms is incomplete and exhibit high affinity for oxygen-containing ligands what provides the opportunity for their chemical modification. Manipulation of the TiO2 nanoparticle surface was found to alter the way nanoparticles interact with light and enhance their chemical reactivity and improving their optical properties in the visible region. These ligands were used as "leads" that bridge the electronic properties of semiconductors to electroactive biomolecules such as DNA or proteins. We have utilized monoclonal anti-EGFR antibodies (C225) for targeting of nanoparticles to the epithelial colon cancer cells. Photoinduced charge separation was than employed to create reactive oxygen species and induce apoptosis in the tumor cells. “Cold light,” or bioluminescence, the same property exhibited by fireflies, was also used to develop localized therapy that is activated only in the cancers, leaving healthy cells intact.
