Richards-Kortum This proposal brings together scientists from very diverse areas with the goal of developing new photonic probes and contrast agents for highly sensitive and selective detection of pre-cancers in vivo . Dr. Andrew Ellington will use the approaches of combinatorial chemistry to develop a library of aptamer molecules specific for biomolecular targets on the surface of cervical cancerous and pre-cancerous cells. He will use well-established cervical cell lines at different stages of cancer development provided by Dr. Lotan. Drs. Brian Korgel and Konstantin Sokolov will develop new photonic probes based on quantum dots (BK) and metal nanoparticles (KS). They will utilize both the aptamers developed by Dr. Ellington as well as well-known antibodies currently used in clinical histopathology. Dr. Rebecca Richards- Kortum will test the conjugates as molecular specific contrast agents using optical microscopy and spectroscopy. She will use cervical cancer cell lines provided by Dr. Lotan, three-dimensional tissue phantoms and fresh cervical tissue slices from Dr. Follen. Experiments with all three biological systems representing properties of normal and neoplastic cervix at different levels of complexity will be used to assess and refine the performance and detection scheme for the new contrast agents. This refinement will include preparing bioengineered aptamers with high affinity to cancer specific targets, tailoring optical properties of metal nanoparticles and quantum dots, optimizing conjugation procedures, and developing optimal imaging geometries.
