THz in Biology and Medicine: Towards Quantifying and Understanding the Interaction of Millimeter Waves with Cells and Cell Processes

Peter Siegel
California Institute of Technology

Monday, April 13, 2009 at 1:00PM
54-134 Engineering IV Building
Refreshments Served

Abstract: Careful evaluation of the impact of millimeter and submillimeter wavelength radiation on biological systems is becoming more relevant as high frequency communications, radar and imaging begin to make their way into commercial applications. Especially apropos is the high power density, pulsed millimeter-wave crowd-control system known as active-denial. Methods to identify and quantify the impact of this radiation on a microscopic scale are just beginning to emerge. In this talk a simple setup is demonstrated for remote temperature monitoring of water, water-based media, and cells exposed to millimeter wave energy. The technique relies on recording changes in the shape of a stretching band of the hydroxyl group in liquid water at 3100 to 3700 cm-1. Temperature changes of 1°C are readily distinguished over a range consistent with cellular processes (25-45°C) using integration times below 10 seconds. The instrument was used to successfully determine the temperature rise of a cluster of H1299 derived human lung cells adhered to polystyrene and immersed in PBS under exposure of RF millimeter wave radiation (60 GHz, 1.3, 2.6 and 5.2 mW/mm2). Following this, our first measurements of low levels of RF power on cell function were performed using a FRET (Forster resonance energy transfer) technique on cells tagged with GFP (green fluorescent protein) to look at the formation of membrane nanopores. Some intriguing early results were obtained.

Biography: Peter Siegel holds appointments as Faculty Associate in Electrical Engineering and Senior Scientist in Biology at Caltech and Technical Group Supervisor, Senior Research Scientist and Principal Engineer for Submillimeter Wave Advanced Technology (SWAT) at the Jet Propulsion Laboratory in Pasadena, California. He has been working in the areas of millimeter and submillimeter-wave technology and applications for more than 30 years and has PI'd or co-I'd more 65 R&D programs and been involved in four major space flight instruments. Among many other duties, he chairs the International Committee for the International Conference on Infrared, Millimeter and Terahertz Waves, the oldest and largest venue devoted to the field of far IR techniques, science and applications. Dr. Siegel is a Fellow of IEEE and has served as an IEEE Distinguished Lecturer and chair of MTT Committee 4-THz Technology and applications. His current interests are split between traditional Earth, planetary and astrophysics applications and new THz applications in medicine and biology.