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Structural and Functional Hierarchy in Photosynthetic Energy Conversion-from Molecules to Nanostructures.

Szabó T, Magyar M, Hajdu K, Dorogi M, Nyerki E, Tóth T, Lingvay M, Garab G, Hernádi K, Nagy L - Nanoscale Res Lett (2015)

Bottom Line: Recently, we adapted several physical and chemical methods for binding RCs to different nanomaterials.It is generally found that the P(+)(QAQB)(-) charge pair, which is formed after single saturating light excitation is stabilized after the attachment of the RCs to the nanostructures, which is followed by slow reorganization of the protein structure.This can be a basis of sensing element of bio-hybrid device for biosensor and/or optoelectronic applications.

View Article: PubMed Central - PubMed

Affiliation: Department of Medical Physics and Informatics, University of Szeged, Rerrich B. tér 1., H-6721, Szeged, Hungary. tiberatosz@gmail.com.

ABSTRACT
Basic principles of structural and functional requirements of photosynthetic energy conversion in hierarchically organized machineries are reviewed. Blueprints of photosynthesis, the energetic basis of virtually all life on Earth, can serve the basis for constructing artificial light energy-converting molecular devices. In photosynthetic organisms, the conversion of light energy into chemical energy takes places in highly organized fine-tunable systems with structural and functional hierarchy. The incident photons are absorbed by light-harvesting complexes, which funnel the excitation energy into reaction centre (RC) protein complexes containing redox-active chlorophyll molecules; the primary charge separations in the RCs are followed by vectorial transport of charges (electrons and protons) in the photosynthetic membrane. RCs possess properties that make their use in solar energy-converting and integrated optoelectronic systems feasible. Therefore, there is a large interest in many laboratories and in the industry toward their use in molecular devices. RCs have been bound to different carrier matrices, with their photophysical and photochemical activities largely retained in the nano-systems and with electronic connection to conducting surfaces. We show examples of RCs bound to carbon-based materials (functionalized and non-functionalized single- and multiwalled carbon nanotubes), transitional metal oxides (ITO) and conducting polymers and porous silicon and characterize their photochemical activities. Recently, we adapted several physical and chemical methods for binding RCs to different nanomaterials. It is generally found that the P(+)(QAQB)(-) charge pair, which is formed after single saturating light excitation is stabilized after the attachment of the RCs to the nanostructures, which is followed by slow reorganization of the protein structure. Measuring the electric conductivity in a direct contact mode or in electrochemical cell indicates that there is an electronic interaction between the protein and the inorganic carrier matrices. This can be a basis of sensing element of bio-hybrid device for biosensor and/or optoelectronic applications.

No MeSH data available.


Related in: MedlinePlus

a Schematic representation of the MWCNT/PTAA/RC complex. RC: photosynthetic reaction centre; PTAA: poly(3)-thiophene acetic acid conducting polymer; MWCNT: multiwalled carbon nanotube. b TEM image and c photochemical activity (monitored by the absorption change at 860 nm). The in the absorption at 860 nm monitors the redox state of the primary electron donor (P+/P). Solid line is calculated by a first-order single-exponential decay with the lifetime of τ = 480 ms
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Fig7: a Schematic representation of the MWCNT/PTAA/RC complex. RC: photosynthetic reaction centre; PTAA: poly(3)-thiophene acetic acid conducting polymer; MWCNT: multiwalled carbon nanotube. b TEM image and c photochemical activity (monitored by the absorption change at 860 nm). The in the absorption at 860 nm monitors the redox state of the primary electron donor (P+/P). Solid line is calculated by a first-order single-exponential decay with the lifetime of τ = 480 ms

Mentions: The major goal of the current research is to find the most efficient systems and conditions for photoelectric energy conversion and for the stability of the RC bio-nanocomposite. We immobilized the RC protein to MWCNTs through specific chemical binding to amine functional groups and through conducting polymer (poly(3)-thiophene acetic acid, PTAA; Fig. 7). An efficient vectorial charge transfer can be driven in the composites by combining the three systems [62].Fig. 7


Structural and Functional Hierarchy in Photosynthetic Energy Conversion-from Molecules to Nanostructures.

Szabó T, Magyar M, Hajdu K, Dorogi M, Nyerki E, Tóth T, Lingvay M, Garab G, Hernádi K, Nagy L - Nanoscale Res Lett (2015)

a Schematic representation of the MWCNT/PTAA/RC complex. RC: photosynthetic reaction centre; PTAA: poly(3)-thiophene acetic acid conducting polymer; MWCNT: multiwalled carbon nanotube. b TEM image and c photochemical activity (monitored by the absorption change at 860 nm). The in the absorption at 860 nm monitors the redox state of the primary electron donor (P+/P). Solid line is calculated by a first-order single-exponential decay with the lifetime of τ = 480 ms
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4666181&req=5

Fig7: a Schematic representation of the MWCNT/PTAA/RC complex. RC: photosynthetic reaction centre; PTAA: poly(3)-thiophene acetic acid conducting polymer; MWCNT: multiwalled carbon nanotube. b TEM image and c photochemical activity (monitored by the absorption change at 860 nm). The in the absorption at 860 nm monitors the redox state of the primary electron donor (P+/P). Solid line is calculated by a first-order single-exponential decay with the lifetime of τ = 480 ms
Mentions: The major goal of the current research is to find the most efficient systems and conditions for photoelectric energy conversion and for the stability of the RC bio-nanocomposite. We immobilized the RC protein to MWCNTs through specific chemical binding to amine functional groups and through conducting polymer (poly(3)-thiophene acetic acid, PTAA; Fig. 7). An efficient vectorial charge transfer can be driven in the composites by combining the three systems [62].Fig. 7

Bottom Line: Recently, we adapted several physical and chemical methods for binding RCs to different nanomaterials.It is generally found that the P(+)(QAQB)(-) charge pair, which is formed after single saturating light excitation is stabilized after the attachment of the RCs to the nanostructures, which is followed by slow reorganization of the protein structure.This can be a basis of sensing element of bio-hybrid device for biosensor and/or optoelectronic applications.

View Article: PubMed Central - PubMed

Affiliation: Department of Medical Physics and Informatics, University of Szeged, Rerrich B. tér 1., H-6721, Szeged, Hungary. tiberatosz@gmail.com.

ABSTRACT
Basic principles of structural and functional requirements of photosynthetic energy conversion in hierarchically organized machineries are reviewed. Blueprints of photosynthesis, the energetic basis of virtually all life on Earth, can serve the basis for constructing artificial light energy-converting molecular devices. In photosynthetic organisms, the conversion of light energy into chemical energy takes places in highly organized fine-tunable systems with structural and functional hierarchy. The incident photons are absorbed by light-harvesting complexes, which funnel the excitation energy into reaction centre (RC) protein complexes containing redox-active chlorophyll molecules; the primary charge separations in the RCs are followed by vectorial transport of charges (electrons and protons) in the photosynthetic membrane. RCs possess properties that make their use in solar energy-converting and integrated optoelectronic systems feasible. Therefore, there is a large interest in many laboratories and in the industry toward their use in molecular devices. RCs have been bound to different carrier matrices, with their photophysical and photochemical activities largely retained in the nano-systems and with electronic connection to conducting surfaces. We show examples of RCs bound to carbon-based materials (functionalized and non-functionalized single- and multiwalled carbon nanotubes), transitional metal oxides (ITO) and conducting polymers and porous silicon and characterize their photochemical activities. Recently, we adapted several physical and chemical methods for binding RCs to different nanomaterials. It is generally found that the P(+)(QAQB)(-) charge pair, which is formed after single saturating light excitation is stabilized after the attachment of the RCs to the nanostructures, which is followed by slow reorganization of the protein structure. Measuring the electric conductivity in a direct contact mode or in electrochemical cell indicates that there is an electronic interaction between the protein and the inorganic carrier matrices. This can be a basis of sensing element of bio-hybrid device for biosensor and/or optoelectronic applications.

No MeSH data available.


Related in: MedlinePlus