Principles of molecular self-assembly into giant hierarchical structures of hundreds of micrometers in size are studied in aggregates of meso-tetra(4-sulfonatophenyl)porphine(TPPS_(4)).The aggregates form a central tu...Principles of molecular self-assembly into giant hierarchical structures of hundreds of micrometers in size are studied in aggregates of meso-tetra(4-sulfonatophenyl)porphine(TPPS_(4)).The aggregates form a central tubular core,which is covered with radially protruding filamentous non-branching aggregates.The filaments cluster and orient at varying angles from the core surface and some filaments form bundles.Due to shape resemblance,the structures are termed giant sea urchin(GSU)aggregates.Spectrally resolved fluorescence microscopy reveals J-and H-bands of TPPS_(4)aggregates in both the central core and the filaments.The fluorescence of the core is quenched while filaments exhibit strong fluorescence.Upon drying,the filament fluorescence gets quenched while the core is less affected,showing stronger relative fluorescence.Fluorescencedetected linear dichroism(FDLD)microscopy reveals that absorption dipoles corresponding to J-bands are oriented along the filament axis.The comparison of FDLD with scanning electron microscopy(SEM)reveals the structure of central core comprised of multilayer ribbons,which wind around the core axis forming a tube.Polarimetric second-harmonic generation(SHG)and thirdharmonic generation microscopy exhibits strong signal from the filaments with nonlinear dipoles oriented close to the filament axis,while central core displays very low SHG due to close to centrosymmetric organization.Large chiral nonlinear susceptibility points to helical arrangement of the filaments.The investigation shows that TPPS_(4)molecules form distinct aggregate types,including chiral nanotubes and nanogranular aggregates that associate into the hierarchical GSU structure,prototypical to complex biological structures.The chiral TPPS_(4)aggregates can serve as harmonophores for nonlinear microscopy.展开更多
基金supported by European Regional Development Fund(No.01.2.2.-LMT-K-718-02-0016)under grant agreement with the Research Council of Lithuania(LMTLT)Support was also provided by the Natural Sciences and Engineering Research Council of Canada(NSERC)(Nos.RGPIN-2017-06923 and DGDND-2017-00099)+1 种基金I.D.was supported by GINOP-2.3.2-15-2016-00058 and G.S.by GINOP-2.3.2-15-2016-00001ELKH KÜ-37/2020 grants from the Hungarian Ministry for National Economy and the Eötvös Loránd Research Network,respectively。
文摘Principles of molecular self-assembly into giant hierarchical structures of hundreds of micrometers in size are studied in aggregates of meso-tetra(4-sulfonatophenyl)porphine(TPPS_(4)).The aggregates form a central tubular core,which is covered with radially protruding filamentous non-branching aggregates.The filaments cluster and orient at varying angles from the core surface and some filaments form bundles.Due to shape resemblance,the structures are termed giant sea urchin(GSU)aggregates.Spectrally resolved fluorescence microscopy reveals J-and H-bands of TPPS_(4)aggregates in both the central core and the filaments.The fluorescence of the core is quenched while filaments exhibit strong fluorescence.Upon drying,the filament fluorescence gets quenched while the core is less affected,showing stronger relative fluorescence.Fluorescencedetected linear dichroism(FDLD)microscopy reveals that absorption dipoles corresponding to J-bands are oriented along the filament axis.The comparison of FDLD with scanning electron microscopy(SEM)reveals the structure of central core comprised of multilayer ribbons,which wind around the core axis forming a tube.Polarimetric second-harmonic generation(SHG)and thirdharmonic generation microscopy exhibits strong signal from the filaments with nonlinear dipoles oriented close to the filament axis,while central core displays very low SHG due to close to centrosymmetric organization.Large chiral nonlinear susceptibility points to helical arrangement of the filaments.The investigation shows that TPPS_(4)molecules form distinct aggregate types,including chiral nanotubes and nanogranular aggregates that associate into the hierarchical GSU structure,prototypical to complex biological structures.The chiral TPPS_(4)aggregates can serve as harmonophores for nonlinear microscopy.
