Update on the EU project proposal
"Characterization of biological samples with Terahertz radiation"

Dear Colleagues,

During the past month I got in contact with several of you regarding the preparation of the proposal (in particular the definition of the various objectives). Let me remind you that the next deadline for the Action "Environment and Health" in the "Quality of Life" programme is March 2000. I am currently trying to do most of the scientific work on the proposal by the end of November, so as to leave the budgetary and administrative part at the end, with a reasonable amount of time available.

Right after the Free Electron Laser Conference in Hamburg at the end of August, I presented the outline of our Project Proposal at a Workshop on Research with Infrared Radiation, organized by the FEL group at FZR-Dresden. On that occasion, interest was expressed by Prof. Dressel from the Uni-Stuttgart, who has a wide range of BWO available for spectroscopic measurements in the range 30 GHz to 1.2 THz, and by the Stanford FEL group, that has already a great expertise on biological and biomedical applications in the FIR. Participation of a partner from outside the EU is now possible in the V Framework Programme, although without direct EU-funding.

The aim of the project is to use terahertz and far infrared radiation to study structural and functional properties of biological molecules, cell membranes, cell nuclei and tissues, to investigate the effects and the potential damage of radiation in these spectral ranges, and to develop applications and devices for bilogical and biomedical imaging.

The project will bridge the existing gap in knowledge about the effects of THz radiation on biological systems. THz radiation covers the frequency range between 0.1 and 10 THz (30 µm to 3 mm), which lies at the boundary between the microwave- and the optical regions of the spectrum.

From the discussion we had so far the activity in the project will follow a stream line of systems with increasing complexity:

Biomolecules - Membranes - Cells - Tissues => Organs

with focus on three main points:

1. Development of spectroscopic techniques for the investigation of a few significant biological systems ("fashionable" enzymes and proteins as well as biological membranes as outlined by W. Maentele at Frankfurt)
2. Test of cell damage as a function of average and peak power and amplitude modulation under exposure with radiation in an extended range from 30 GHz to 30 THz
3. Development of devices and instrumentation to be used in "cell biology"

It may be useful to point out that a project on the development of imaging systems at THz frequencies, coordinated by Martin Chamberlain at Uni-Leeds, has been recently funded in the first call of the Information Society and Technology Programme for an amount of abourt about 2 MEuro.

Point 2) and in particular point 3) of the present proposal can be linked to the activities planned in the IST project. Specific contributions were outlined to me by Don Arnone from Toshiba Cambridge, which is currently the only organisation to our knowledge engaged in medical imaging using Terahertz radiation. The link to points 1) to 3) is expressed by Toshiba as:

1) an understanding of the Terahertz spectral response of proteins, enzymes, etc. that lead to contrast in images of teeth, skin, etc.

2) the development of a portable spectrometer capable of rapidly analysing bio-fluids and performing chemical analysis (if this proves possible in the far and mid infrared).

3) conducting safety trials for Terahertz imaging. The company is aware that non-thermal effects may play a role when THz radiation is applied to imaging techniques, and is interested in discovering the limitations in advance.

From Sept. 29 to October 2 I attended a workshop in Naples, which was organised by the Italian Health Physics Association (AIRP) and entirely devoted to non-ionizing e.m. radiation and related issues. On that occasion I visited the Biology Lab of Maria Rosaria Scarfi at CNR-IRECE and discussed with her the identification of simple and significant biological samples to be used in genotoxic studies. Human lymphocytes would be a suitable sample, for which comparative results are available at ELF and Microwave frequencies. A rapid evaluation of potential cytogenetic damage can be performed by employing the so-called Micro-Nuclei (MN) test technique. More information on the exposure requirements and measurement techniques will be made available by the Naples group. We also discussed issues like sample preparation, storage, transportation (when needed), irradiation modalities, etc. M. R. Scarfì pointed out that the Naples group could participate in the proposal as member of ICEmB, the Italian Interuniversity Centre for Interaction between Electromagnetic fields and Biosystems. This will strengthen the proposal, since additional support will be available by a number of participating institutions in the biophysical and biomedical field.

The following week (Oct.7 and 8) I visited Werner Maentele at the Biophysics Institute in Frankfurt to work on the proposal (identification of systems to investigate by spectroscopic measurements). On Oct. 8 Martin Dressel (Stuttgart) and Eckart Grosse (FZR-Dresden) joined us in the discussion. I also briefly visited Dressel lab in Stuttgart. During the meeting in Frankfurt we put down the lay out of the proposal with a first draft of the three "Workpackages" (to use the EC forms terminology). From the discussion it also resulted that the equipment available at Stuttgart (BWOs and FTIR spectrometer) can easily be employed in spectroscopic measurements on biological samples using existing setup. The Biophysics Institute in Frankfurt is located just close to various medical institutes. Contacts and collaborations already exist with various groups. W. Maentele will check the possibility of involving a group of hematologists.

Further work is needed to define the various tasks, and, in particular, we need a clear definition of point 3) -Development of devices and instrumentation to be used in "cell biology"- This part of the proposal is important, since it adds technological value to the research through the Toshiba participation. However, particular care has to be taken in describing the role of Toshiba and Uni-Leeds in this project to avoid major overlaps with the work carried out in the TERAVISION project. We should formulate and establish a link rather than any overlap.

A comparison of the various near-field microscopy techniques could be a good central task within point 3). It can provide useful information about limits in resolution at various wavelength. The work in progress at CLIO and at Stanford on the SNIPER technique fit nicely in this part.

The group at Stanford can also play an important role in establishing a contact with the interdisciplinary large scale initiative going on at Stanford to bring together physicists, biochemists and biologists (see Phys. World - February 1999)

G.P. Gallerano

Frascati, 19.10.1999