Ultrasensitive Optical Absorption Spectroscopy with Biomolecules

California Institute Of Technology, Pasadena CA

Investigators

Abstract

This award supports further development of an instrument based on use of a Fabry-Perot for cavity-enhanced spectroscopy of biological molecules. The instrument will use an extremely high-finesse optical cavity to enhance the sensitivity of laser absorption spectroscopy, in a configuration that allows the study of molecules in liquid solvents or in phospholipid membranes. This approach has the potential to be able to provide information about the dynamic behavior of individual biological molecules, an important theme in modern biology. The device will be tested using bacteriochlorophyll, one component of the bacterial photosynthetic reaction center. Although much is known about the dynamics of electron transfer and the atomic structure of such reaction centers, the information comes from studies of the bulk properties of large numbers of molecules. Information about dynamics of individual molecules has the potential to provide substantial improvement in understanding of the interrelationship of structure and function in the reaction center. The broader impacts of this research reflect both the participation of graduate and undergraduate students from a wide range of academic disciplines and, as a result of the biophysical research activities that the instrument will make possible, high visibility in the quantum optics and optical metrology communities. This visibility is likely to encourage greater technical cross-fertilization between these fields and the biological sciences. An acceleration of the development of highly sophisticated optical instrumentation for biological experiments could have substantial impact on the future progress of the technology used in biological research.