title: Investigation of the photobleaching process of eosin Y in aqueous solution by thermal lens spectroscopy.
abstract: Eosin Y is known to be a powerful probe of biological molecules and an efficient photosensitizing agent for the production of singlet molecular oxygen. Under continuous laser excitation, degradation through photobleaching is observed in aqueous solutions of eosin Y; this process is driven by the production of singlet oxygen. Optical bleaching in aqueous solutions is known to yield anomalous thermal lens transient signals, which can be evaluated by modeling the relaxation processes that give rise to the generation of heat in the solution. A model describing photobleaching in the thermal lens transient signal is derived and is applied to investigate eosin Y in aqueous solutions at different temperatures. Using this model, quantitative information regarding the molecular diffusion rate, optical bleaching, and fluorescence quantum efficiency is obtained.
authors: Departamento de Física, Universidade Estadual de Maringá, Av. Colombo 5790, Maringá - PR, 87020-900, Brazil. herculano@osamember.org
authors: L S
authors: LS
authors: Herculano
authors: L C
authors: LC
authors: Malacarne
authors: V S
authors: VS
authors: Zanuto
authors: G V B
authors: GV
authors: Lukasievicz
authors: O A
authors: OA
authors: Capeloto
authors: N G C
authors: NG
authors: Astrath
mesh_terms: D004801:Eosine Yellowish-(YS) / Q000737:chemistry*; D007700:Kinetics; D008958:Models, Molecular; D038761:Photobleaching; D026082:Singlet Oxygen / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D026082:Singlet Oxygen; D004801:Eosine Yellowish-(YS)