Artificial photosynthetic reaction center

Figure 1. Schematic representation of the artificial photosynthetic reaction center by a monolayer assembly by A-S-D triad and antenna molecules for light harvesting (H), lateral energy migration and energy transfer, and charge separation across the membrane via multistep electron transfer (a) Side view of mono-layer assembly, (b) top view of a triad surrounded by H molecules, and (c) energy diagram for photo-electric conversion in a monolayer assembly.

In the present review, first we will describe how to fabricate artificial photosynthetic reaction center in nanometer scales by making use of phase separation in mixed monolayers of hydrocarbon (HC) and fluorocarbon (FC) amphiphiles [2,5,20-26] as shown in Fig. 2b [3]. The phase separated structures were studied by SPMs such as AFM, SSPM, and scanning near-field optical/atomic force microscopy (SNOAM) [27-33] as well as a conventional local surface analysis by SIMS [3,5], The model anionic and cationic HC amphiphilic... 

Figure 4. Detection of the change in photo-induced surface dipole moments in highly oriented A-S-D triads in artificial photosynthetic reaction centers as the local surface potential change in nano-domains measured by SSPM.

Imahori H, Guldi DM, Tamaki K et al (2001) Charge separation in a novel artificial photosynthetic reaction center lives 380 ms. J Am Chem Soc 123 6617-6628... 

Imahori, H., Guldi, D. M., Tamaki, K., Yoshida, Yutaka, L., Chuping, S., Yoshiteru, F., and Shunichi (2001) Charge Separation in a Novel Artificial Photosynthetic Reaction Center Lives 380 ms, J. Amer. Chem. Soc. 123,6617-6628. 

Bioinspired Supramolecular Device and Self-Assembly for Artificial Photosynthetic Reaction Center... 

Figure 25. (A) Structure of an artificial photosynthetic reaction center, the molecular triad C-P-Q, and the proton-shuttling quinone, Qsl (B) Schematic diagram showing orientation of the triad In the liposome and the sequence of events after photoexcitation (see table at right and text for details) (C) Fluorescence excitation spectra of the pH-indicator dye pyraninetrisulphonate as a measure of the concentration of the protonated form of the indicator dye (D) Fluorescence excitation-band intensity as a function of irradiation time in the absence and in the presence of FCCP. Figures adapted from Steinberg-Yfrach, Liddeii, Hung, (AL) Moore, Gust and (TA) Moore (1997) Conversion of light energy to proton potential in liposomes by artificial photosynthetic reaction centres. Natu re 385 239-241.

In the early 1980s we designed an artificial photosynthetic reaction center that overcomes this problem by using a multistep electron transfer strategy such as that found in natural reaction centers (Moore et al, 1984). More recently, molecular triad 9 which consists of a porphyrin chromophore (P) bound covalently to a naphthoquinone derivative (NQ) and a carotenoid electron donor (C) was designed both to undergo multistep electron transfer and to organize... 

Gust D, Moore TA, Moore AL, Kuciauskas D, Liddell PA and Halbert BD (1997b) Mimicry of carotenoid photoprotection in artificial photosynthetic reaction centers Triplet-triplet energy transfer by a relay mechanism. J. Photochem Photobiol 43 209-216... 

Hu YZ, Tsukiji S, Shinkai S, Oishi S, Hamachi I (2000) Construction of artificial photosynthetic reaction centers on a protein surface vectorial, multistep, and proton-coupled electron transfer for long-lived charge separation. J Am Chem Soc 122 241-253... 

Fig. 31 Schematic representation of the artificial photosynthetic reaction center by a monolayer assembly of antenna (H) and A-S-D triad molecules for light harvesting, energy migration and transfer, and charge separation via multistep electron transfer.

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