Table of Contents
Laser Chemistry
Volume 2007, Article ID 36024, 5 pages
Research Article

Photostability of Uranine via Crossed-Beam Thermal Lens Technique

1Department of Laser Applications in Metrology, Photochemistry, and Agriculture, National Institute of Laser Enhanced Sciences (NILES), Cairo University, Giza 12613, Egypt
2Department of Physics, Faculty of Science, Cairo University, Giza 12613, Egypt

Received 2 October 2006; Revised 9 February 2007; Accepted 22 February 2007

Academic Editor: Savas Georgiou

Copyright © 2007 M. Zein El-Din et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Uranine is a diagnostic aid in ophthalmology and is used as an immunohistological stain. A photostability study on this important compound using a crossed-beam thermal lens (TL) technique was carried out. The study is based on the photodegradation (PD) behavior and rate regarding some experimental parameters such as the incident laser power, wavelength, modulation frequency, and sample concentration. The effects of such parameters on the TL signal and PD rate are discussed in details. It has been found that the PD rate is proportional to the power of the pumping laser and the concentration of the sample within the investigated range. However, the modulation frequency is found not to influence the PD rate. The photochemical quantum yield has been measured using potassium ferrioxalate actinometry and it was found to be very low.