New applications of lasers in photobiology and photochemistry

Photonics spectra and optical medical diagnostic field for examination of biological tissues generally and human body specially cover many spectroscopic and laser technologies based on NIR spectroscopy, fluorescence and Raman spectroscopy, Optical coherent tomography (OCT), Confocal microscopy, Opto-acoustic tomography, photon correlation spectroscopy and imaging, and Speckle monitoring of biological flows. The recent achievements in light scattering and coherent light effects in tissues, and in the design of novel lasers and fiber optic techniques for examination of biological tissues are the real motive and the attracting factor for many labs to consider the mentioned above techniques. Our lab, as it contains most of these facilities, started to use these technologies since 1997 in several applications: 1. Applying a suitable setup for introducing exogenous DNA of pAB (with bar/ Gus gene) into cells of embryonic collie of Egyptian wheat based on 193 and 608 nm, 6 ns Excimer laser pulses introducing a modified procedure of Laser-Mediated gene transfer in Egyptian wheat Tridum Aestivum. 2. Applying laser technologies in early identification of abnormal tissues spectroscopically 3. We considered several types of tissues starting with breast cancer, which was subjected to intensive spectroscopic studies using NIR, MIR, FIR, Raman spectroscopy as well as photo-acoustic spectroscopy and imaging studies. Cell carcinoma was considered using Raman spectroscopy and a clear distinction between normal tissue before and after introduction of cell cancer as well as after treating of the tissues using PDT. 4. The application of 193 nm Excimer laser pulse to study photolysis of Acetone using time resolved spectroscopy. A locally designed setup was used to study the effect of delay time (1 mu s, 2 mu s,...., 10 mu s...... 50 mu s) on the CO and CH3 radicals resulting from the photolysis.