Effect of light intensity and wavelengths on photodegradation reactions of riboflavin in aqueous solution.

摘要: Abstract A study of the effect light intensity and wavelengths on photodegradation reactions riboflavin (RF) solutions in presence phosphate buffer using three UV visible radiation sources has been made. The rates magnitude two major (i.e., photoaddition photoreduction) depend as well irradiation. Photoaddition is facilitated by yields cyclodehydroriboflavin (CDRF) whereas photoreduction results from normal photolysis yielding lumichrome (LC) lumiflavin (LF). ratios photoproducts at 2.0 M concentration, CDRF/RF (0.09–0.22) CDRF/LC (0.54–1.75), vary with source are higher than those radiation. On contrary, LF/LC (0.15–0.25) increase changing to visible. rate much faster causing 25% degradation a 10 −5  M solution 7.5 min compared that radiations 150–330 min.