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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Photochemical behavior of Safranine-Riboflavin complex in the degradation of folic acid

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Author(s):
Santos, Willy G. [1] ; Scurachio, Regina S. [1] ; Cardoso, Daniel R. [1]
Total Authors: 3
Affiliation:
[1] Univ Sao Paulo, Inst Quim Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil
Total Affiliations: 1
Document type: Journal article
Source: JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY; v. 293, p. 32-39, NOV 1 2014.
Web of Science Citations: 9
Abstract

The photochemistry of safranine complexed with riboflavin and the photoinduced electron transfer from folic acid to the complex were investigated by steady-state and time resolved absorption spectroscopy, and the photoproducts were further analyzed by LC-orbitrap-FT-MS. UV-vis spectra of the complex showed a decrease in the safranine band at 520 nm with increasing concentration of riboflavin, which was attributed to complex formation. A 1:1 (safranine:riboflavin) stoichiometry was determined using Job's method. Following safranine photoexcitation, there is formation of a radical pair in the complex by donation of an electron from ground-state riboflavin to excited-state safranine. The cation radical of riboflavin within this complex reacts with folic acid to yield FA(+){*}, which may accept an electron from the anion radical of safranine, avoiding the photobleaching of the safranine. In contrast, the reaction of the anion radical of non-complexed safranine with folic acid leads to safranine photobleaching. (C) 2014 Elsevier B.V. All rights reserved. (AU)

FAPESP's process: 09/54040-8 - Acquisition of a high-resolution Orbitrap mass spectrometer for the discovery and structural analysis of biologically active compounds: applications in proteomics, biomarkers, synthesis, isolation, and characterization of natural products, studies of redox systems in food and enzymatic synthesis
Grantee:Emanuel Carrilho
Support type: Multi-user Equipment Program
FAPESP's process: 12/19823-4 - Phototransients of organoboranes generated by photolysis and flavin sensitization
Grantee:Willy Glen Santos
Support type: Scholarships in Brazil - Post-Doctorate