University of California, Riverside

Department of Electrical and Computer Engineering



Investigating Membrane Nanoelectromechanics by Optical Technologies


Investigating Membrane Nanoelectromechanics by Optical Technologies
 
Bahman Anvari
Department of Bioengineering, Rice University

Date: April 11, 2005
Time: 1:00 pm
Location: Bourns Hall A265

One of the hallmarks of life is motion. In the auditory system, the cochlear outer hair cells (OHCs) within the organ of Corti exhibit rapid (as high as 80 kHz) electrically-induced movements known as electromotility, a process required for normal hearing. Recently, a transmembrane protein, prestin, specifically expressed in OHCs has been discovered. When expressed in non-auditory mammalian cells, prestin-transfected cells are endowed with electromotility, and exhibit reciprocal electromechanical behavior, characteristics of a piezoelectric-like material.

Using a novel experimental approach that combines optical trapping with voltage-clamp and fluorescence imaging techniques on a single platform, we have demonstrated that native biological membranes are capable of electrically-induced pico-Newton level force generation in the absence of specialized transmembrane proteins such as prestin over a broad range of electrical excitation frequency. This force generation is enhanced in the presence of prestin; is dependent on membrane tension and the transmembrane electrical potential; and diminishes in the presence of a specific anionic amphipathic agent, salicylate.

Our long-term objectives are to understand the molecular basis of electromotility, and investigate how membrane-based electromechanical coupling can be modulated in a controlled manner through changes in membrane physical properties and membrane-prestin interactions. Characterizing the nanoelectromechanical properties of plasma membranes, and understanding the contribution of prestin to electromotility has the potential to not only lead to a better understanding of the hearing process and development of therapeutics for specific types of hearing loss, but also to the development of biological nano-electromechanical systems with diagnostics and therapeutic applications.

Biography:

Dr. Bahman Anvari received his B.A. in Biophysics from University of California-Berkeley in 1985, M.S. in Biomedical Engineering from California State University, Sacramento in 1988, and Ph.D. in Bioengineering from Texas A&M University in 1993. He was a postdoctoral researcher at the Beckman Laser Institute and Medical Clinic, University of California, Irvine, and later a Research Assistant professor of Engineering at Harvey Mudd College. He joined the Department of Bioengineering at Rice University in 1998 as an Assistant professor where he is currently an Associate Professor.

Dr. Anvari’s research interests involve the use of photonic technologies to study nanoelectromechanical phenomena within the auditory system, and development of optically-based methods for biomedical imaging and therapeutic applications. He has published more than 200 scientific articles including over 50 peer-reviewed manuscripts. His research has been supported by The Whitaker Foundation, National Science Foundation, the National Institutes of Health, and industry. At Rice University, he has developed and taught courses in Biomedical Engineering Instrumentation, and Biophotonics. Dr. Anvari is an Associate Editor for the Annals of Biomedical Engineering and a fellow of the American Society for Lasers in Surgery and Medicine. He holds four patents.
More in Colloquia

More Information 

General Campus Information

University of California, Riverside
900 University Ave.
Riverside, CA 92521
Tel: (951) 827-1012

Department Information

Electrical and Computer Engineering
Suite 343 Winston Chung Hall
University of California, Riverside
Riverside, CA 92521-0429

Tel: (951) 827-2484
Fax: (951) 827-2425
E-mail: E-mail/Questions

Footer