Colloquia

Biophotonics and Nanobiotechnology: Impact on Health Care

This talk will present our multidisciplinary research in Biophotonics and discuss how this field, together with nanobiotechnology, is impacting healthcare. Biophotonics utilizes light-matter interactions for ultrasensitive bioimaging and biosensing as well as for light guided and activated therapies such as photodynamic therapy and photocleavable drug delivery1-3. We are utilizing multimodal and multispectral imaging involving a combination of nonlinear optical phenomena such as two-photon absorption, coherent anti-stokes Raman scattering (CARS), second harmonic and sum frequency generation. They allow chemically selective imaging and probing of the local macromolecular content in biological specimens for a molecular understanding of cellular processes and diseases. Moreover, the ability to monitor macromolecular distributions and interactions is indispensable for drug discovery.

A major issue in biophotonics is limited penetration of light in biological media. A novel direction to overcome this is the use of nonlinear process for in-situ photon generation of desired wavelength for light activation. Our new concept of in-situ photon conversion by nonlinear process to excite a photosensitizer for photodynamic therapy will be discussed. Utilization of up-converting rare-earth ion doped nanoparticles with sequential multiphoton processes, allows for in-situ NIR-to-NIR conversion, suitable for contrast bioimaging of biological media, and NIR-to-U.V conversion, suitable for light induced release of drugs.

Nanobiophotonics is emerging as a major thrust area of nanobiotechnology which utilizes nanoprobes and nanocarriers for bioimaging, sensing, and light activated of therapy. Nanomedicine adds a novel dimension to nanobiotechnology, as it utilizes nanostructured materials for combined actions of therapy and diagnostic, called theranostics3. Multifunctional nanoplatforms containing multiple imaging and sensing probes are being developed which will enable the integration of cellular, tissue level and whole body imaging using a single formulation. Coupled with a therapeutic payload, they provide the ability to act in the treatment (drug or light based) of a disease and provide real time for optically monitoring the efficacy of the treatment. We are developing light guided gene/siRNA delivery nanoplatforms for application in other major health care issues such as infectious diseases (e.g. swine flu, HIV, Malaria), aging disorders, drug addiction, chronic pain, depression and obesity.

This talk will conclude with a discussion of new opportunities in these frontiers.

1. P.N. Prasad “Introduction to Biophotonics”, John Wiley & Sons, New York (2003)
2. P.N. Prasad “Nanophotonics”, John Wiley & Sons, New York (2004)
3. P.N. Prasad “Introduction to Nanomedicine and Nanobioengineering”, JohnWiley & Sons, New York (2012)