Photoinduced Hydrogen Evolution with Hydrogenase and Water-soluble Viologen-linked Zinc Porphyrins

A series of water-soluble viologen-linked zinc porphyrins with different methylene chain lengths (n = 3−6) between porphyrin and viologen, ZnP ( C n V )4, were synthesized and characterized. The intra- molecular electron transfer rate constants from the porphyrin moiety of ZnP (Cn V )4 to viologen were measured by using fluorescence lifetime and laser flash photolysis. Both the photoexcited singlet state and the triplet state of the porphyrin were quenched by the bonded viologen. These compounds were applied to photoinduced hydrogen evolution in the system containing nicotinamide-adenine dinucleotide phosphate (reduced form NADPH), ZnP ( C n V )4 and hydrogenase under steady-state irradiation.

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Determination of association constants by laser flash photolysis between Zn-TPPS3 and bipyridinium salts in photocatalytic hydrogen evolution systems

Journal of Molecular Catalysis ◽

10.1016/0304-5102(85)85040-9 ◽

1985 ◽

Vol 32 (1) ◽

pp. 119-123 ◽

Cited By ~ 4

Author(s):

Ichiro Okura ◽

Naruhiko Kaji ◽

Shigetoshi Aono ◽

Akira Yamada

Keyword(s):

Hydrogen Evolution ◽

Flash Photolysis ◽

Laser Flash Photolysis ◽

Laser Flash ◽

Association Constants ◽

Photocatalytic Hydrogen Evolution ◽

Evolution Systems

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Photochemical reactions of metal nitrosyl complexes. Mechanisms of NO reactions with biologically relevant metal centers

International Journal of Photoenergy ◽

10.1155/s1110662x01000204 ◽

2001 ◽

Vol 3 (3) ◽

pp. 161-169 ◽

Cited By ~ 7

Author(s):

Peter C. Ford

Keyword(s):

Flash Photolysis ◽

Laser Flash Photolysis ◽

Nitrogen Monoxide ◽

Laser Flash ◽

Photochemical Reactions ◽

Water Soluble ◽

Hypoxic Cell ◽

Biological Targets ◽

Nitrosyl Complexes ◽

Metal Nitrosyl

The discoveries that nitric oxide (a.k.a. nitrogen monoxide) serves important roles in mammalian bioregulation and immunology have stimulated intense interest in the chemistry and biochemistry of NO and derivatives such as metal nitrosyl complexes. Also of interest are strategies to deliver NO to biological targets on demand. One such strategy would be to employ a precursor which displays relatively low thermal reactivity but is photochemically active to release NO. This proposition led us to investigate laser flash and continuous photolysis kinetics of nitrosyl complexes such as the Roussin's iron-sulfur-nitrosyl cluster anionsFe2S2(NO)42−andFe4S3(NO)7−and several ruthenium salen and porphyrin nitrosyls. These include studies using metal-nitrosyl photochemistry as a vehicle for delivering NO to hypoxic cell cultures in order to sensitizeγ-radiation damage. Also studied were the rates and mechanisms of NO “on” reactions with model water soluble heme compounds, the ferriheme protein met-myoglobin and various ruthenium complexes using ns laser flash photolysis techniques. An overview of these studies is presented.

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Direct measurement by laser flash photolysis of intramolecular electron transfer in the three-electron reduced form of ascorbate oxidase from zucchini

Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology ◽

10.1016/0167-4838(94)90174-0 ◽

1994 ◽

Vol 1208 (1) ◽

pp. 166-170 ◽

Cited By ~ 15

Author(s):

J.T. Hazzard ◽

A. Marchesini ◽

P. Curir ◽

G. Tollin

Keyword(s):

Electron Transfer ◽

Direct Measurement ◽

Flash Photolysis ◽

Laser Flash Photolysis ◽

Laser Flash ◽

Reduced Form ◽

Ascorbate Oxidase ◽

Intramolecular Electron Transfer

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New functionalized water-soluble benzophenones: a laser flash photolysis study

Canadian Journal of Chemistry ◽

10.1139/v85-498 ◽

1985 ◽

Vol 63 (11) ◽

pp. 3001-3006 ◽

Cited By ~ 22

Author(s):

D. J. Lougnot ◽

P. Jacques ◽

J. P. Fouassier ◽

H. L. Casal ◽

Nguyen Kim-Thuan ◽

...

Keyword(s):

Water Solubility ◽

Flash Photolysis ◽

Laser Flash Photolysis ◽

Homogeneous Solution ◽

High Water ◽

Laser Flash ◽

Water Soluble ◽

Triplet States ◽

Decay Kinetics ◽

Triplet Ground State

Two water-soluble ionic benzophenones containing a quatemized amine and a sulphonate group have been investigated by laser flash photolysis. The decay kinetics and spectra of their triplet states were studied and quenching constants by triethanolamine, isopropanol, and methyl viologen determined. These data are of interest when these benzophenones are used as initiators for photo-polymerizing water-soluble acrylates in homogeneous solution or in reverse micellar assemblies. The high water solubility of these compounds allows the bimolecular deactivations due to triplet–triplet (kTT) and triplet–ground state (kSQ) interactions to be determined more accurately than in the case of benzophenone itself.

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