title: Characterization of the transient species generated by the photoexcitation of C-phycocyanin from Spirulina platensis: a laser photolysis and pulse radiolysis study.
abstract: Nanosecond laser flash photolysis and pulse radiolysis were used to generate and characterize the triplet state and cation radical of C-phycocyanin (C-PC) from Spirulina platensis. The transient absorption spectra of C-PC were measured from direct excitation and acetone sensitization in aqueous solution at room temperature by KrF (248 nm) laser flash photolysis. Laser-induced transient species have been characterized by the method of acetone sensitization and one-electron oxidation. In nitrous oxide-saturated phosphate buffer saline (pH = 7.0) of C-PC, the produced intermediates are assigned to the excited triplet state and the radical cation. Using acetone as photosensitizer, the C-PC excited triplet states produced via triplet-triplet energy transfer and the C-PC radical cation from electron transfer reaction were further confirmed. Furthermore, the corresponding kinetic parameters were determined. To our knowledge, the transient absorption spectra of C-PC have been reported for the first time.
authors.affiliation: Center for Molecular Science, Institute of Chemistry, The Chinese Academy of Sciences, Beijing.
authors.forename: S P
authors.initials: SP
authors.lastname: Zhang
authors.forename: S P
authors.initials: SP
authors.lastname: Qian
authors.forename: J Q
authors.initials: JQ
authors.lastname: Zhao
authors.forename: S D
authors.initials: SD
authors.lastname: Yao
authors.forename: L J
authors.initials: LJ
authors.lastname: Jiang
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry*; D010084:Oxidation-Reduction; D010782:Photolysis; D010798:Phycocyanin / Q000737:chemistry*; D011675:Pulse Radiolysis; D053545:Spirulina
chemical_list: D001426:Bacterial Proteins; D010798:Phycocyanin