title: Fructose as a novel photosensitizer: Characterization of reactive oxygen species and an application in degradation of diuron and chlorpyrifos.
abstract: The objective of this study was to identify reactive oxygen species (ROS) generated from the exposure of fructose solution to the 254 nm ultraviolet (UV) light and evaluate whether fructose can be used as a photosensitizer for accelerated photo-degradation of diuron and chlorpyrifos. We demonstrated that hydrogen peroxide, singlet oxygen ((1)O2) and acidic photolysis products were generated upon UV exposure of fructose. Consistent with these findings, UV induced degradation of chlorpyrifos and diuron was accelerated by the presence of 500 mM fructose. The average first order photo-degradation rate constants in the absence and presence of 500 mM fructose were 0.92 and 2.07 min(-1) respectively for diuron and 0.04 and 0.07 min(-1) for chlorpyrifos. The quantum yields (ɸ) for direct photo-degradation of diuron and chlorpyrifos were 0.003 and 0.001 respectively. In the presence of 500 mM fructose, these values increased to 0.006 and 0.002 respectively. Thus, fructose may be an effective photosensitizer.
authors.affiliation: Program in Culinary and Food Science, Drexel University, Philadelphia, PA, USA.
authors.forename: Shaila
authors.initials: S
authors.lastname: Nayak
authors.affiliation: Department of Nutrition Sciences, Drexel University, Philadelphia, PA, USA.
authors.forename: Juan
authors.initials: J
authors.lastname: Muniz
authors.affiliation: Civil, Architectural and Environmental Engineering, Drexel University, Philadelphia, PA, USA.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Sales
authors.affiliation: Department of Nutrition and Food Science, University of Maryland-College Park, MD, USA. Electronic address: rtikekar@umd.edu.
authors.forename: Rohan V
authors.initials: RV
authors.lastname: Tikekar
mesh_terms: D004390:Chlorpyrifos / Q000032:analysis / Q000737:chemistry*; D004237:Diuron / Q000032:analysis / Q000737:chemistry*; D005632:Fructose / Q000737:chemistry / Q000528:radiation effects; D006861:Hydrogen Peroxide / Q000737:chemistry; D010782:Photolysis; D017319:Photosensitizing Agents / Q000737:chemistry / Q000528:radiation effects; D017382:Reactive Oxygen Species / Q000737:chemistry; D012996:Solutions; D014466:Ultraviolet Rays
chemical_list: D017319:Photosensitizing Agents; D017382:Reactive Oxygen Species; D012996:Solutions; D005632:Fructose; D004237:Diuron; D006861:Hydrogen Peroxide; D004390:Chlorpyrifos
keywords: Advanced oxidative process; Chlorpyrifos; Diuron; Fructose; Photosensitizer; Ultraviolet light