Photostability of Uranine via Crossed-Beam Thermal Lens Technique

Abstract

Uranine is a diagnostic aid in ophthalmology and used as immuno‐histological stain. Photostability study on such important compound using crossed‐beam thermal lens (TL) technique was carried out. The study is based on the photodegradation (PD) behavior and rate regarding some 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. The rate of PD is found to be proportional to the power of the pumping laser and concentration of the sample within the investigated range. 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.