Anisotropic Organization and Microscopic Manipulation of Self-Assembling Synthetic Porphyrin Microrods That Mimic Chlorosomes: Bacterial Light-Harvesting Systems

作者：Chappaz Gillot Cyril; Marek Peter L; Blaive Bruno J; Canard Gabriel; Buerck Jochen; Garab Gyozo; Hahn Horst; Javorfi Tamas; Kelemen Lorand; Krupke Ralph; Moessinger Dennis; Ormos Pal; Reddy Chilla Malla; Roussel Christian; Steinbach Gabor; Szabo Milan; Ulrich Anne S; Vanthuyne Nicolas; Vijayaraghavan Aravind; Zupcanova Anita; Balaban Teodor Silviu^*

来源：Journal of the American Chemical Society, 2012, 134(2): 944-954.

DOI：10.1021/ja203838p

Being able to control in time and space the positioning, orientation, movement, and sense of rotation of nano- to micro-scale objects is currently an active research area in nanoscience, having diverse nanotechnological applications. In this paper, we demonstrate unprecedented control and maneuvering of rod-shaped or tubular nanostructures with high aspect ratios which are formed by self-assembling synthetic porphyrins. The self-assembly algorithm, encoded by appended chemical-recognition groups on the periphery of these porphyrins, is the same as the one operating for chlorosomal bacteriochlorophylls (BChl%26apos;s). Chlorosomes, rod-shaped organelles with relatively long-range molecular order, are the most efficient naturally occurring light-harvesting systems.(1,2) They are used by green photosynthetic bacteria to trap visible and infrared light of minute intensities even at great depths, e.g., 100 m below water surface or in volcanic vents in the absence of solar radiation. In contrast to most other natural light-harvesting systems, the chlorosomal antennae are devoid of a protein scaffold to orient the BChl%26apos;s; thus, they are an attractive goal for mimicry by synthetic chemists, who are able to engineer more robust chromophores to self-assemble. Functional devices with environmentally friendly chromophores-which should be able to act as photosensitizers within hybrid solar cells, leading to high photon-to-current conversion efficiencies even under low illumination conditions have yet to be fabricated. The orderly manner in which the BChl%26apos;s and their synthetic counterparts self-assemble imparts strong diamagnetic and optical anisotropies and flow/shear characteristics to their nanostructured assemblies, allowing them to be manipulated by electrical, magnetic, or tribomechanical forces.

• 出版日期2012-1-18